V4L/DVB (5304): Improve chip matching in v4l2_register

The chip matching in struct v4l2_register for VIDIOC_DBG_G/S_REGISTER 
was rather primitive. It could not be extended to other busses besides 
i2c and it lacked a way to.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/saa7115.c b/drivers/media/video/saa7115.c
index c4f066d..7735b67 100644
--- a/drivers/media/video/saa7115.c
+++ b/drivers/media/video/saa7115.c
@@ -1425,7 +1425,7 @@
 	{
 		struct v4l2_register *reg = arg;
 
-		if (reg->i2c_id != I2C_DRIVERID_SAA711X)
+		if (!v4l2_chip_match_i2c_client(client, reg->match_type, reg->match_chip))
 			return -EINVAL;
 		if (!capable(CAP_SYS_ADMIN))
 			return -EPERM;