[X86]Fix wrong asm match for VMASKMOVDQU

VMASKMOVDQU supports 32bit/64bit version in 64bitmode, previously we prefer to use VMASKMOVDQU64 in 64bitmode because the 32bit one need 0x67 prefix.
After D150436, asm match table changed a little, which makes in 64bit mode "vmaskmovdqu     %xmm0, %xmm1" will match VMASKMOVDQU other than VMASKMOVDQU64, this patch correct the asm match order for this instruction.

Reviewed By: skan

Differential Revision: https://reviews.llvm.org/D150835