[X86][SSE] Fix an issue with PEXTRW/PEXTRB indices during shuffle combining

We were checking that the index was in range of the destination vector type, not the (larger) source vector type


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304894 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed