frontends/va: Fix missing unlock
What does this MR do and why?
frontends/va: Fix missing unlock
Fix defect reported by Coverity Scan.
Missing unlock (LOCK) missing_unlock: Returning without unlocking drv->mutex.
Fixes: af695149 ("frontends/va: pass in film_grain_target as new output") Signed-off-by: Vinson Lee vlee@freedesktop.org