avcodec/msmpeg4dec: Reuse identical RL VLCs

avcodec/msmpeg4dec: Reuse identical RL VLCs

Some of the RLTables used by msmpeg4dec actually coincide with other
RLTables: ff_rl_table[5] coincides with ff_h263_rl_inter (and
ff_rl_table[2] with ff_mpeg4_rl_intra). Given that ff_h263_rl_inter is
always initialized before msmpeg4dec's RLTables are initialized, one can
just reuse the VLC tables by copying the pointers; after all, there are
no ownership issues for static data. This saves 70912B from the .bss
segment, translating into actual memory savings when this decoder is
actually used.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>