fix regression on pre-BDW platform.
fix regression on pre-BDW platform.

ivb/hsw will spit the 32X32 to two simd8 instructions, and noMask
instruction introduced there, the if-opt pass shouldn't change the
predicate state for no mask instructions.

v2: fix typo.
Signed-off-by: Luo Xionghu <c3dafbeb50547b880155fb36e6f40d38b44f6611@intel.com>
Reviewed-by: Yang Rong <78759e37dc7114caed18f74e7515c5cb519dbf6d@intel.com>

wdv4758h/beignet,wdv4758h/beignet,wdv4758h/beignet,wdv4758h/beignet,wdv4758h/beignet