V4L/DVB: v4l2-common: add ability to use v4l2_ctrl_query_fill for chroma gain

Add the ability to use the v4l2_ctrl_query_fill() function for the newly
introduced chroma gain control.

Also, make use of the centralized function by the one caller.

This work was sponsored by EyeMagnet Limited.

Signed-off-by: Devin Heitmueller <dheitmueller@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/v4l2-common.c b/drivers/media/video/v4l2-common.c
index e679834..6a3d0b7 100644
--- a/drivers/media/video/v4l2-common.c
+++ b/drivers/media/video/v4l2-common.c
@@ -429,6 +429,7 @@
 	case V4L2_CID_SHARPNESS:		return "Sharpness";
 	case V4L2_CID_BACKLIGHT_COMPENSATION:	return "Backlight Compensation";
 	case V4L2_CID_CHROMA_AGC:		return "Chroma AGC";
+	case V4L2_CID_CHROMA_GAIN:		return "Chroma Gain";
 	case V4L2_CID_COLOR_KILLER:		return "Color Killer";
 	case V4L2_CID_COLORFX:			return "Color Effects";
 	case V4L2_CID_AUTOBRIGHTNESS:		return "Brightness, Automatic";
@@ -622,6 +623,7 @@
 	case V4L2_CID_BLUE_BALANCE:
 	case V4L2_CID_GAMMA:
 	case V4L2_CID_SHARPNESS:
+	case V4L2_CID_CHROMA_GAIN:
 	case V4L2_CID_RDS_TX_DEVIATION:
 	case V4L2_CID_AUDIO_LIMITER_RELEASE_TIME:
 	case V4L2_CID_AUDIO_LIMITER_DEVIATION: