media: dvb: tag deprecated DVB APIs as such

There are three headers at DVB that should not be used on
future projects: audio.h, osd.h and video.h.

While this is already clear at the docs, make clear also at
the headers that those files should not be used on future
drivers.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

include/uapi/linux/dvb/audio.h

 /* SPDX-License-Identifier: LGPL-2.1+ WITH Linux-syscall-note */
 /*
- * audio.h
+ * audio.h - DEPRECATED MPEG-TS audio decoder API
+ *
+ * NOTE: should not be used on future drivers
  *
  * Copyright (C) 2000 Ralph  Metzler <ralph@convergence.de>
  *                  & Marcus Metzler <marcus@convergence.de>

include/uapi/linux/dvb/osd.h

 /* SPDX-License-Identifier: LGPL-2.1+ WITH Linux-syscall-note */
 /*
- * osd.h
+ * osd.h - DEPRECATED On Screen Display API
+ *
+ * NOTE: should not be used on future drivers
  *
  * Copyright (C) 2001 Ralph  Metzler <ralph@convergence.de>
  *                  & Marcus Metzler <marcus@convergence.de>

include/uapi/linux/dvb/video.h

 /* SPDX-License-Identifier: LGPL-2.1+ WITH Linux-syscall-note */
 /*
- * video.h
+ * video.h - DEPRECATED MPEG-TS video decoder API
+ *
+ * NOTE: should not be used on future drivers
  *
  * Copyright (C) 2000 Marcus Metzler <marcus@convergence.de>
  *                  & Ralph  Metzler <ralph@convergence.de>