[X86] Update VBMI2 vshld/vshrd tests to use an immediate that doesn't require a modulo.

Planning to replace these with funnel shift intrinsics which would mask out the extra bits. This will help minimize test diffs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@350504 91177308-0d34-0410-b5e6-96231b3b80d8
6 files changed