[media] tm6000: add radio support to the driver

Changes:
  Add function tm6000_set_reg_mask for change some bits in regs. Very usefull, simplify some code with this function.
  Add control mute
  Add control volume
  Add control audio input MUX
  Add support radio

Radio works well. TV works too

Known bugs:
  The programm gnomeradio can't set freq for radio, it use old v4l API. Audio over USB works via arecord.
  The programm mplayer can set freq but no any audio
           mplayer -v -rawaudio rate=48000 radio://105.2/capture

 driver=v4l2:alsa:adevice=hw.1,0:amode=1:audiorate=48000:forceaudio:immediatemode=0
  When start watch TV very shortly after radio the kernel crashed hardly. Didn't stop all USB URBs, need some time for stop.

[mchehab@redhat.com: fix merge conflicts]

Signed-off-by: Beholder Intl. Ltd. Dmitry Belimov <d.belimov@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>