[media] s5p-fimc: Don't use mutex_lock_interruptible() in device release()

Use uninterruptible mutex_lock in the release() file op to make
sure all resources are properly freed when a process is being
terminated. Returning -ERESTARTSYS has no effect for a terminating
process and this caused driver resources not to be released. Not
releasing the buffer queue also prevented other drivers to free
memory, e.g. in MMAP -> USERPTR scenario.
This patch is required for stable kernels v3.6+.

Reported-by: Kamil Debski <[e-mail]>
Reported-by: Marek Szyprowski <[e-mail]>
Signed-off-by: Sylwester Nawrocki <[e-mail]>
Signed-off-by: Kyungmin Park <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/platform/s5p-fimc/fimc-capture.c

···
 
 	dbg("pid: %d, state: 0x%lx", task_pid_nr(current), fimc->state);
 
-	if (mutex_lock_interruptible(&fimc->lock))
-		return -ERESTARTSYS;
+	mutex_lock(&fimc->lock);
 
 	if (--fimc->vid_cap.refcnt == 0) {
 		clear_bit(ST_CAPT_BUSY, &fimc->state);

drivers/media/platform/s5p-fimc/fimc-m2m.c

···
 	dbg("pid: %d, state: 0x%lx, refcnt= %d",
 		task_pid_nr(current), fimc->state, fimc->m2m.refcnt);
 
-	if (mutex_lock_interruptible(&fimc->lock))
-		return -ERESTARTSYS;
+	mutex_lock(&fimc->lock);
 
 	v4l2_m2m_ctx_release(ctx->m2m_ctx);
 	fimc_ctrls_delete(ctx);