Revert "[X86][SSE] Generalize X86ISD::BLENDI support to more value types"

This reverts commit r353610.
It causes a miscompile visible in macro expansion in a bootstrapped clang.

http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20190211/626590.html

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353699 91177308-0d34-0410-b5e6-96231b3b80d8
19 files changed