X86: Make sure that we have SSE4.1 before we generate insertps nodes.

PR19721.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208552 91177308-0d34-0410-b5e6-96231b3b80d8
Remove the always true UseCFI member.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208553 91177308-0d34-0410-b5e6-96231b3b80d8