Fixes out of array read
Fixes: asan_heap-oob_177e222_885_cov_1532528832_MERGE_D_TI_3.bit
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit 9f9440bd81)
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
tags/n2.4.4