msm: vidc: Skip processing of release buffer event

When clients call Close command without Flush, FW tries to flush
the output buffers internally and return FBD's and release buffer
reference events. These events are not meaningful to clients which
already called close. Processing these events at this stage causes
unnecessary confusion and deadlocks. Hence drop them.

Change-Id: I9a8850d20321024d1db481e37247163c3ae31044
Signed-off-by: Praneeth Paladugu <ppaladug@codeaurora.org>
Signed-off-by: Hui YU <huiyQuic@codeaurora.org>