LD/testsuite: Also discard `.MIPS.options' in orphan tests

LD/testsuite: Also discard `.MIPS.options' in orphan tests

Complement commit 5b5f4e6f8cd2 ("ld: Early detection of orphans we know
will be discarded") and add `.MIPS.options' to the list of sections
discarded with orphan tests, removing failures like:

./ld-new: error: unplaced orphan section `.MIPS.options' from `tmpdir/orphan-11.o'.
FAIL: ld-elf/orphan-11

and:

./ld-new: error: unplaced orphan section `.MIPS.options' from `tmpdir/orphan-12.o'.
FAIL: ld-elf/orphan-12

from n64 MIPS testing.

	ld/
	* testsuite/ld-elf/orphan-11.ld: Also discard `.MIPS.options'
	sections.