[FastISel][X86] Refactor XALU folding. NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211735 91177308-0d34-0410-b5e6-96231b3b80d8
The includes were sorted. Revert r210578.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211737 91177308-0d34-0410-b5e6-96231b3b80d8
[FastISel][X86] More refactoring of select lowering and XALU folding. NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211740 91177308-0d34-0410-b5e6-96231b3b80d8