[X86] Add PR40318 shuffle test case

The other test case is already covered by the PR40306 test case, which was mainly concerned with SSSE3 codegen.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351201 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed