ituh263: reject b-frame with pp_time = 0

Avoid a division by 0 in ff_mpeg4_set_one_direct_mv.

Sample-Id: 00000168-google
Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind

Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
Merge remote-tracking branch 'qatar/master'

* qatar/master:
  ituh263: reject b-frame with pp_time = 0

See: bb01be80462adcf4900c925e25bc644e512a4b7b
Merged-by: Michael Niedermayer <michaelni@gmx.at>
avformat/avidec: Use a buffer with sufficient padding in read_gab2_sub()

Fixes out of array read
Fixes: 0ff9841c2a102f06e0d582bfc3376cbd-asan_heap-oob_495589_6836_cov_1763916974_mewmew_ssa.avi
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>