ld: Don't xfail ld-elf/warn[12] on 64-bit Solaris/SPARC
Two ld tests currently XPASS on 64-bit Solaris/SPARC:
XPASS: ld-elf/warn1
XPASS: ld-elf/warn2
They were xfail'ed on Solaris/SPARCv9 back in 2005
https://sourceware.org/pipermail/binutils/2005-February/039268.html
but obviously this no longer appplies.
Fixed by removing the xfail's.
Tested on sparcv9-sun-solaris2.11 and sparc-sun-solaris2.11.
* testsuite/ld-elf/warn1.d: Don't xfail on 64-bit Solaris/SPARC.
* testsuite/ld-elf/warn2.d: Likewise.