[media] v4l2: add core support for the new VIDIOC_ENUM_FREQ_BANDS ioctl

This adds the usual core support code for this new ioctl.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/include/media/v4l2-ioctl.h b/include/media/v4l2-ioctl.h
index 19e9352..e614c9c 100644
--- a/include/media/v4l2-ioctl.h
+++ b/include/media/v4l2-ioctl.h
@@ -230,6 +230,8 @@
 					struct v4l2_frequency *a);
 	int (*vidioc_s_frequency)      (struct file *file, void *fh,
 					struct v4l2_frequency *a);
+	int (*vidioc_enum_freq_bands) (struct file *file, void *fh,
+				    struct v4l2_frequency_band *band);
 
 	/* Sliced VBI cap */
 	int (*vidioc_g_sliced_vbi_cap) (struct file *file, void *fh,