media: imx7-media-csi: don't store a floating pointer

if imx7_csi_try_fmt() fails, cc variable won't be
initialized and csi->cc[sdformat->pad] would be pointing
to a random location.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Rui Miguel Silva <rui.silva@linaro.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/staging/media/imx/imx7-media-csi.c

@@ -1051,7 +1051,9 @@ static int imx7_csi_set_fmt(struct v4l2_subdev *sd,
 		goto out_unlock;
 	}
 
-	imx7_csi_try_fmt(csi, cfg, sdformat, &cc);
+	ret = imx7_csi_try_fmt(csi, cfg, sdformat, &cc);
+	if (ret < 0)
+		goto out_unlock;
 
 	fmt = imx7_csi_get_format(csi, cfg, sdformat->pad, sdformat->which);
 	if (!fmt) {