msm: vidc: Ensure firmware released all buffers in error case

Ensure firmware released all buffers before driver flush out
all buffers in error case to avoid failures due to firmware
accessing the flushed out buffer.

Change-Id: If8bed2452276513bf31c9274550ec4743d828f8f
Signed-off-by: Maheshwar Ajja <majja@codeaurora.org>