ttaenc: fix packet size

Signed-off-by: Paul B Mahol <onemda@gmail.com>
movenc: make uuids static const

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avformat/matroskaenc: make 2 tables static that are not used outside matroskaenc

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