[LegalizeDAG] ExpandLegalINT_TO_FP - cleanup UINT_TO_FP i64 -> f32 expansion.

Use SrcVT/DestVT types and correct shift type.

Part of prep work for D52965

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@345158 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed