media: coda: don't overwrite h.264 profile_idc on decoder instance

On a decoder instance, after the profile has been parsed from the stream
__v4l2_ctrl_s_ctrl() is called to notify userspace about changes in the
read-only profile control. This ends up calling back into the CODA driver
where a missing check on the s_ctrl caused the profile information that has
just been parsed from the stream to be overwritten with the default
baseline profile.

Later on the driver fails to enable frame reordering, based on the wrong
profile information.

Fixes: 347de126d1da (media: coda: add read-only h.264 decoder
                     profile/level controls)
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/platform/coda/coda-common.c

@@ -1803,7 +1803,8 @@ static int coda_s_ctrl(struct v4l2_ctrl *ctrl)
 		break;
 	case V4L2_CID_MPEG_VIDEO_H264_PROFILE:
 		/* TODO: switch between baseline and constrained baseline */
-		ctx->params.h264_profile_idc = 66;
+		if (ctx->inst_type == CODA_INST_ENCODER)
+			ctx->params.h264_profile_idc = 66;
 		break;
 	case V4L2_CID_MPEG_VIDEO_H264_LEVEL:
 		/* nothing to do, this is set by the encoder */