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 ()
c9c5c889174cf7979e5b52d79370606dc3'>tree</a><a href='/guix/commit/gnu/packages.scm?id=a1f211c9c5c889174cf7979e5b52d79370606dc3'>commit</a><a href='/guix/diff/gnu/packages.scm?id=a1f211c9c5c889174cf7979e5b52d79370606dc3'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/gnu/packages.scm'>
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<div class='path'>path: <a href='/guix/log/?id=a1f211c9c5c889174cf7979e5b52d79370606dc3'>root</a>/<a href='/guix/log/gnu?id=a1f211c9c5c889174cf7979e5b52d79370606dc3'>gnu</a>/<a href='/guix/log/gnu/packages.scm?id=a1f211c9c5c889174cf7979e5b52d79370606dc3'>packages.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/gnu/packages.scm?id=a1f211c9c5c889174cf7979e5b52d79370606dc3&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2024-12-12 23:23:33 +0100'>2024-12-12</span></td><td><a href='/guix/commit/gnu/packages.scm?id=97e7e47d6f1e036e1ed6bd3f428e40d9794a3353'>packages: Optimize ‘all-packages’.</a><span class='msg-avail'>...<span class='msg-tooltip'>On my laptop, wall-clock time for (all-packages) goes from 27s to 1s.

* gnu/packages.scm (all-packages): Use a hash table to remember visited
packages instead of calling ‘delete-duplicates’ on the final list.

Change-Id: I4aae804656b56ef2095993e91f0572a5891f419f
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2024-12-01 20:14:15 +0100'>2024-12-01</span></td><td><a href='/guix/commit/gnu/packages.scm?id=4b5dae8defe4c0d5e98b5ce6abba853007485f23'>packages: Factorize ‘all-packages’.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages.scm (all-packages): New procedure.
* etc/source-manifest.scm (all-packages): Remove.
* guix/scripts/graph.scm (all-packages): Remove.
* guix/scripts/refresh.scm (all-packages): Remove.
* guix/scripts/weather.scm (all-packages): Remove.

Change-Id: I6072952c4b877b541037ce86402cfb7744eeb0a0
</span></span></td><td>Ludovic Courtès</td></tr>