[PowerPC] Fix the int2fp(fp2int(x)) DAGCombine to ignore ppc_fp128

This DAGCombine was creating custom SDAG nodes with an illegal ppc_fp128
operand type because it was triggering on f64/f32 int2fp(fp2int(ppc_fp128 x)),
but shouldn't (it should only apply to f32/f64 types). The result was a crash.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@245530 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed