checkasm: Extend mc testing for any combination of 2-32 x 2-32, for OBMC
checkasm: Extend mc testing for any combination of 2-32 x 2-32, for OBMC

av1-1-b8-00-quantizer-55, -56 and -59 actually invokes the mc function
with e.g. 2x16.

videolan/dav1d