[x86] allow 64-bit extracted vector element integer stores on a 32-bit system

With SSE2, we can generate a 'movq' or other 64-bit store op on a 32-bit system
even though 64-bit integers are not legal types.

So instead of producing this:

  pshufd	$229, %xmm0, %xmm1      ## xmm1 = xmm0[1,1,2,3]
  movd	%xmm0, (%eax)
  movd	%xmm1, 4(%eax)

We can do:

  movq %xmm0, (%eax)

This is a fix for the problem noted in D7296.

Differential Revision: http://reviews.llvm.org/D9134

llvm-svn: 235460