avformat/mpc: attempt to allocate a packet that is not smaller than the data inside it

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit 86a9370e2b91d67375e66a06d6eb573b5a017775)

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
1 file changed