This is in preparation for moving the fields only used
by H.263-based decoders from MPVContext to H263DecContext.
For now only the decode_mb function pointer has been moved
(to be able to switch said callback to use an H263DecContext*).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
It avoids checks and allows to make ff_wmv2_decode_mb() static;
furthermore, it allows to avoid a config_components.h inclusion.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
