[SelectionDAG] Add VT consistency checks to the creation of ISD::FMA.
[SelectionDAG] Add VT consistency checks to the creation of ISD::FMA.

This is similar to what is done for binops. I don't know if this would have helped us catch the bug fixed in r336566 earlier or not, but I figured it couldn't hurt.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@336576 91177308-0d34-0410-b5e6-96231b3b80d8

GPUOpen-Drivers/llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,llvm-mirror/llvm,apple/swift-llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,apple/swift-llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,apple/swift-llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,apple/swift-llvm