Install everything in PREFIX, set EXTRA_PATH to find it there.

--- ./Makefile.in~	2016-02-06 01:29:16.595090365 +0100
+++ ./Makefile.in	2016-02-06 09:29:04.286008931 +0100
@@ -133,9 +133,9 @@
 # require for testing here (like TCLX_LIBRARY).
 #========================================================================

-EXTRA_PATH	= $(top_builddir):$(TCL_BIN_DIR)
+EXTRA_PATH	= $(top_builddir):$(TCL_BIN_DIR):$(libdir)
 #EXTRA_PATH     = $(top_builddir):$(TCL_BIN_DIR):$(TK_BIN_DIR)
-TCLLIBPATH      = $(top_builddir)
+TCLLIBPATH      = $(pkglibdir)
 TCLSH_ENV	= TCL_LIBRARY=`@CYGPATH@ $(TCL_SRC_DIR)/library` \
 		  @LD_LIBRARY_PATH_VAR@="$(EXTRA_PATH):$(@LD_LIBRARY_PATH_VAR@)" \
 		  PATH="$(EXTRA_PATH):$(PATH)" \
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<div class='path'>path: <a href='/guix/log/?id=ad64b09df4bcf0a57753c9ad2cdd442b78e205d3&amp;showmsg=1'>root</a>/<a href='/guix/log/gnu?id=ad64b09df4bcf0a57753c9ad2cdd442b78e205d3&amp;showmsg=1'>gnu</a>/<a href='/guix/log/gnu/packages?id=ad64b09df4bcf0a57753c9ad2cdd442b78e205d3&amp;showmsg=1'>packages</a>/<a href='/guix/log/gnu/packages/node.scm?id=ad64b09df4bcf0a57753c9ad2cdd442b78e205d3&amp;showmsg=1'>node.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/node.scm?id=ad64b09df4bcf0a57753c9ad2cdd442b78e205d3'>Collapse</a>)</th><th class='left'>Author</th></tr>
<tr class='logheader'><td><span title='2020-02-26 21:52:47 +0100'>2020-02-26</span></td><td class='logsubject'><a href='/guix/commit/gnu/packages/node.scm?id=5cfc6a88e9fbb9f34855ebd43264266b0201ce50'>gnu: node: Disable failing tests on armhf-linux.</a></td><td>Marius Bakke</td></tr>
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* gnu/packages/node.scm (node)[arguments]: When building on
armhf-linux, disable several zlib tests.


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<tr class='logheader'><td><span title='2020-02-26 21:52:47 +0100'>2020-02-26</span></td><td class='logsubject'><a href='/guix/commit/gnu/packages/node.scm?id=458c3ff552005cbf69ed4a1daee3529214ae73cf'>gnu: node: Update to 10.19.0.</a></td><td>Marius Bakke</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* gnu/packages/node.scm (node): Update to 10.19.0.
[inputs]: Remove LIBUV and NGHTTP2:LIB.  Add LIBUV/LATEST and
NGHTTP2-1.40:LIB.


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<tr class='logheader'><td><span title='2020-02-24 17:10:22 +0100'>2020-02-24</span></td><td class='logsubject'><a href='/guix/commit/gnu/packages/node.scm?id=b4481f2df1ac0e24a41a06671e99e88a5e2c9d2d'>gnu: node: Increase build timeouts.</a></td><td>Marius Bakke</td></tr>
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* gnu/packages/node.scm (node)[properties]: Add MAX-SILENT-TIME.  Increase
TIMEOUT from 3600 seconds to 14400.


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<tr class='logheader'><td><span title='2020-02-10 20:18:05 +0100'>2020-02-10</span></td><td class='logsubject'><a href='/guix/commit/gnu/packages/node.scm?id=51583265394fdab4fecf2710dcf142cd3793c692'>gnu: node: Disable flaky test.</a></td><td>Marius Bakke</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* gnu/packages/node.scm (node)[arguments]: Delete test that fails sporadically.


</td></tr>