[PowerPC] FreeBSD does not require f128 in its data layout string.

Long double is 64 bits on FreeBSD PPC, so the f128 entry is superfluous.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185583 91177308-0d34-0410-b5e6-96231b3b80d8