atomisp: don't let it go past pipes array

In practice, IA_CSS_PIPE_ID_NUM should never be used when
calling atomisp_q_video_buffers_to_css(), as the driver should
discover the right pipe before calling it.

Yet, if some pipe parsing issue happens, it could end using
it.

So, add a WARN_ON() to prevent such case.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/staging/media/atomisp/pci/atomisp_fops.c

@@ -221,6 +221,9 @@ int atomisp_q_video_buffers_to_css(struct atomisp_sub_device *asd,
 	unsigned long irqflags;
 	int err = 0;
 
+	if (WARN_ON(css_pipe_id >= IA_CSS_PIPE_ID_NUM))
+		return -EINVAL;
+
 	while (pipe->buffers_in_css < ATOMISP_CSS_Q_DEPTH) {
 		struct videobuf_buffer *vb;