avviddec: Fix size of linesize parameter
Although avcodec_align_dimensions2()
only copies 4 ints, it expects
a buffer of at least AV_NUM_DATA_POINTERS
(8) ints.
Although avcodec_align_dimensions2()
only copies 4 ints, it expects
a buffer of at least AV_NUM_DATA_POINTERS
(8) ints.