[X86] Remove an unused isel pattern that looked for pshufd with v4f32 type.
[X86] Remove an unused isel pattern that looked for pshufd with v4f32 type.

I don't believe our current lowering/combining would ever produce such a node. We only produce integer typed pshufds.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@319068 91177308-0d34-0410-b5e6-96231b3b80d8

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