Re: Add some expected failures for bfin linker tests

After commit 7ade0f15 I was seeing bfin-elf +XPASS: weak symbols,
and on looking into the bfin targets a little, discovered we have two
bfin-linux targets.  One, bfin-uclinux, is like bfin-elf in that
ld -m elf32bfin is the default, and the other, bfin-linux-uclibc where
ld -m elf32bfinfd is the default.  So putting bfin-*-*linux* in test
xfails or elsewhere is wrong.  We want bfin-*-linux* instead to just
select the fdpic bfin target.

This patch corrects wrong bfin target triples in the ld testsuite,
not just the recent change but others I'd added to xfails too.
It also fixes the bfin-linux-uclibc ld-elf/64ksec fail