My earlier change broke Solaris testing, because @FLOCK@ isn't substituted
just into libgomp/Makefile where it worked, but also the
testsuite/libgomp-site-extra.exp file where Make variables aren't present
and can't be substituted.

The following patch instead computes the absolute srcdir path and uses it
for FLOCK.

2024-01-10  Jakub Jelinek  <jakub@redhat.com>

	PR libgomp/113192
	* configure.ac (FLOCK): Use $libgomp_abs_srcdir/testsuite/flock
	instead of \$(abs_top_srcdir)/testsuite/flock.
	* configure: Regenerated.