JVET-O0428: check lmcs aps id in multiple slices of same picture
Additional changes over MR926 to address comments for the case if the first slice has slice_lmcs_enabled_flag = 0, and the following slice has slice_lmcs_enabled_flag = 1.
Additional changes over MR926 to address comments for the case if the first slice has slice_lmcs_enabled_flag = 0, and the following slice has slice_lmcs_enabled_flag = 1.