ffmpeg_filter: replace exit() by exit_program()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
ffmpeg_opt: replace exit() by exit_program()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
cmdutils: replace exit() by exit_program()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Check the return value of ff_rv34_decode_init() in rv30.c and rv40.c

Avoids possible null pointer dereferences on oom.

Fixes ticket #2727.