vectorized VMACF
vectorized VMACF

New VMACF with manually written SSE2 is 45 instructions.

Old VMACF with auto-vectorized C code was 91 instructions.

mupen64plus/mupen64plus-rsp-cxd4,mupen64plus/mupen64plus-rsp-cxd4,mupen64plus/mupen64plus-rsp-cxd4