V4L/DVB (7166): [v4l] Add new user class controls and deprecate others

These were removed in commit 26d507fc

:

> -#define V4L2_CID_HCENTER               (V4L2_CID_BASE+22)
> -#define V4L2_CID_VCENTER               (V4L2_CID_BASE+23)
> -#define V4L2_CID_LASTP1                        (V4L2_CID_BASE+24) /*
> last CID + 1 */
> +
> +/* Deprecated, use V4L2_CID_PAN_RESET and V4L2_CID_TILT_RESET */
> +#define V4L2_CID_HCENTER_DEPRECATED    (V4L2_CID_BASE+22)
> +#define V4L2_CID_VCENTER_DEPRECATED    (V4L2_CID_BASE+23)

But there was no warning in Documentation/feature-removal-schedule.txt
and I'm receiving reports that it's breaking userspace apps (the
gstreamer-v4l2 plugin breaks in Fedora rawhide). You can't just pull
things from the published userspace API like that.

Please can we revert the addition of _DEPRECATED to these ioctl
definitions. Perhaps we can add a runtime warning if they actually get
used? Or a compile-time warning if we can manage that?

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>