ld: testsuite: Enable ld-elfweak tests on Solaris/x86

The ld-elfweak tests are currently only enabled on Solaris/SPARC for no
apparent reason.  Enabling them on Solaris in general lets them all PASS
on both amd64-pc-solaris2.11 and i386-pc-solaris2.11.

2025-07-25  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>

	ld:
	* testsuite/ld-elfweak/elfweak.exp: Enable on *-*-solaris2* rather
	than sparc*-*-solaris2* only.