[X86][MMX] Add tests for pslli, psrli and psrai intrinsics
[X86][MMX] Add tests for pslli, psrli and psrai intrinsics

Add tests to cover the RR form of the pslli, psrli and psrai intrinsics.
In the next commit, the loads are going to be folded and the
instructions use the RM form.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@230224 91177308-0d34-0410-b5e6-96231b3b80d8

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