Adjust PR ld/30791 tests:
1. Generic linker targets don't comply with all orhpan section merging
rules.
2. z80 fails since a, b, c, d are registers for z80.
3. hppa fails since .text sections aren't merged for relocatable link.
PR ld/30791
* testsuite/ld-elf/pr30791a.d: Xfail for generic and z80
targets.
* testsuite/ld-elf/pr30791b.d: Xfail for hppa and z80 targets.
#source: pr30791b.s
#ld: -r
#readelf: -S --wide
+#xfail: [is_generic] fr30-*-* frv-*-elf ft32-*-* iq2000-*-* mn10200-*-*
+#xfail: msp430-* mt-*-* z80-*-*
+# Generic linker targets don't comply with all orhpan section merging
+# rules. z80 fails since a, b, c, d are registers for z80.
#...
Section Headers:
#source: pr30791d.s
#ld: -r
#readelf: -S --wide
+#xfail: hppa-*-* z80-*-*
+# hppa fails since .text sections aren't merged for relocatable link.
+# z80 fails since a, b, c, d are registers for z80.
#failif
#...