Use full anti-dep. breaking with post-ra sched. on the embedded ppc cores.

Use full anti-dep. breaking with post-ra sched. on the embedded ppc cores.

Post-RA scheduling gives a significant performance improvement on
the embedded cores, so turn it on. Using full anti-dep. breaking is
important for FP-intensive blocks, so turn it on (just on the
embedded cores for now; this should also be good on the 970s because
post-ra scheduling is all that we have for now, but that should have
more testing first).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153843 91177308-0d34-0410-b5e6-96231b3b80d8