JVET-O0220 method-1: Parse merge_subblock_flag conditioned on MaxNumSubblockMergeCand
JVET-O0220 method-1: Parse merge_subblock_flag conditioned on MaxNumSubblockMergeCand (Align SW to spec text).
JVET-O0220 method-1: Parse merge_subblock_flag conditioned on MaxNumSubblockMergeCand (Align SW to spec text).