Fix required by suitesparse to build Mongoose

The CMakeLists.txt of Mongoose assumes that SuiteSparse_config has been
installed into the suitesparse source directory, which is not the case
for us, as we are building suitesparse out-of-tree.

SuiteSparse_config can instead be found in the ${CMAKE_INSTALL_PREFIX}
directory.

diff --git a/Mongoose/CMakeLists.txt b/Mongoose/CMakeLists.txt
index 7e134ab..76fa9e2 100644
--- a/Mongoose/CMakeLists.txt
+++ b/Mongoose/CMakeLists.txt
@@ -148,10 +148,10 @@ set(CMAKE_CXX_STANDARD 11)
 #set(CMAKE_CXX_STANDARD_REQUIRED ON)

 # determine which SuiteSparse_config to use
-if (EXISTS ${PROJECT_SOURCE_DIR}/../SuiteSparse_config)
-    message(STATUS "External ../SuiteSparse_config" ${BoldBlue} " found" ${ColourReset} ".")
+if (EXISTS ${CMAKE_INSTALL_PREFIX})
+    message(STATUS "External SuiteSparse_config" ${BoldBlue} " found" ${ColourReset} ".")
     set ( SUITESPARSE_CONFIG_DIR ${PROJECT_SOURCE_DIR}/../SuiteSparse_config )
-    link_directories ( ${PROJECT_SOURCE_DIR}/../lib )
+    link_directories ( ${CMAKE_INSTALL_PREFIX}/lib )
     message ( STATUS "Note: ../SuiteSparse_config must be compiled before compiling Mongoose" )
     set ( SUITESPARSE_CONFIG_LIBRARY suitesparseconfig )
 else ()
uix/log/etc/disarchive-manifest.scm?showmsg=1'>log</a><a href='/guix/tree/etc/disarchive-manifest.scm?id=4987618368679f420dc89fda35a339d68d80761b'>tree</a><a href='/guix/commit/etc/disarchive-manifest.scm?id=4987618368679f420dc89fda35a339d68d80761b'>commit</a><a href='/guix/diff/etc/disarchive-manifest.scm?id=4987618368679f420dc89fda35a339d68d80761b'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/etc/disarchive-manifest.scm'>
<input type='hidden' name='id' value='4987618368679f420dc89fda35a339d68d80761b'/><input type='hidden' name='showmsg' value='1'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=4987618368679f420dc89fda35a339d68d80761b&amp;showmsg=1'>root</a>/<a href='/guix/log/etc?id=4987618368679f420dc89fda35a339d68d80761b&amp;showmsg=1'>etc</a>/<a href='/guix/log/etc/disarchive-manifest.scm?id=4987618368679f420dc89fda35a339d68d80761b&amp;showmsg=1'>disarchive-manifest.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/etc/disarchive-manifest.scm?id=4987618368679f420dc89fda35a339d68d80761b'>Collapse</a>)</th><th class='left'>Author</th></tr>
<tr class='logheader'><td><span title='2023-10-08 23:43:49 +0200'>2023-10-08</span></td><td class='logsubject'><a href='/guix/commit/etc/disarchive-manifest.scm?id=aa65f31ed2a36a57f047651ff429eb9a7dfb0dcc'>disarchive-manifest: Add one manifest entry per tarball.</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
This works around a situation where ‘cuirass remote-worker’ now builds
with max-jobs = 1 (Cuirass commit
980ef610989895be5ac2ba7f9d1901e5c7f22934).  The effect is that all
.dis.drv would be performed sequentially, on a single machine (‘cuirass
remote-server’ is unable to distribute those derivations to several
machines because it only “sees” the ‘disarchive-collection’ derivation).
This would take a lot of time and force a rebuild of all of *.dis.drv
every time because their build results would not be retrieved by the
‘remote-server’ process.

* etc/disarchive-manifest.scm (disarchive-collection): Remove.
&lt;top level&gt;: Define ‘disarchives’.  Append it to the entries of the
manifest.


</td></tr>
<tr class='logheader'><td><span title='2022-08-06 23:14:41 +0200'>2022-08-06</span></td><td class='logsubject'><a href='/guix/commit/etc/disarchive-manifest.scm?id=eab5366e679c149cf0a5abeb9a196700b171d9da'>disarchive-manifest: Exclude the Chromium tarball.</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* etc/disarchive-manifest.scm (disarchive-collection): Exclude
"chromium-" tarballs.


</td></tr>
<tr class='logheader'><td><span title='2022-08-05 15:28:02 +0200'>2022-08-05</span></td><td class='logsubject'><a href='/guix/commit/etc/disarchive-manifest.scm?id=6d4a0ccecb58c62a95f7f36fa2f4fa53dd52312e'>disarchive-manifest: Filter out origins without a hash.</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* etc/disarchive-manifest.scm (disarchive-collection): Filter out
origins with a phony hash.


</td></tr>
<tr class='logheader'><td><span title='2022-08-05 00:14:29 +0200'>2022-08-05</span></td><td class='logsubject'><a href='/guix/commit/etc/disarchive-manifest.scm?id=2acffd56a58c01785ea6ea738b79991c0685d364'>disarchive-manifest: Handle tar.xz archives.</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* etc/disarchive-manifest.scm (tarball-origin?): Add ".tar.xz".


</td></tr>
<tr class='logheader'><td><span title='2021-10-09 01:02:18 +0200'>2021-10-09</span></td><td class='logsubject'><a href='/guix/commit/etc/disarchive-manifest.scm?id=2ad1ef844632b7605ad6dd362e947a122a0a3925'>disarchive-manifest: Provide valid 'version' string.</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* etc/disarchive-manifest.scm &lt;top level&gt;: Turn 'version' field into a
string.


</td></tr>
<tr class='logheader'><td><span title='2021-09-14 11:50:58 +0200'>2021-09-14</span></td><td class='logsubject'><a href='/guix/commit/etc/disarchive-manifest.scm?id=98712c14fe3517a48603a12eb2e64db305a54fe5'>etc: Add 'disarchive-manifest.scm'.</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* etc/disarchive-manifest.scm: New file.
* Makefile.am (EXTRA_DIST): Add it.


</td></tr>