avcodec/decode: Fix leaks upon subtitle decoding errors

Up until now, various subtitle decoders have not cleaned up
the AVSubtitle on error; this task must not be left to the user
because the documentation explicitly states that the AVSubtitle
"must be freed with avsubtitle_free if *got_sub_ptr is set"
(which it isn't on error).
Leaks happen upon failure in ff_ass_add_rect() or in
ass_decode_frame(); freeing generically also allows to remove
now redundant freeing code in pgssubdec and dvbsubdec.
While just at it, also reset got_sub_ptr generically on error.

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

0 files changed, 0 insertions, 0 deletions