LF-365 [8QM_MEK/8QXP_MEK]mxc:vpu_malone: need skip tsm when skip not decoded frame

- If frame ID is  MEDIA_PLAYER_SKIPPED_FRAME_ID, need skip this frame,
  also need skip its tsm at the same time.
- Fixed coverity issue: CID 6344236 (#2 of 2): Buffer not null
  terminated (BUFFER_SIZE_WARNING).
- Remove two deaded code about ctx pointer check.

Signed-off-by: Shijie Qin <shijie.qin@nxp.com>
Acked-by: ming_qian <ming.qian@nxp.com>
(cherry picked from commit 3cc1c455699e456c11118f3ed60b7fc85f1fd61b)