ALSA: fm801: propagate TUNER_ONLY bit when autodetected

The commit d7ba858a (ALSA: fm801: implement TEA575x tuner autodetection)
brings autodetection to the driver. However the autodetection algorithm misses
the TUNER_ONLY bit if it is supplied by the user.

Thus, user gets weird messages and no card registered.

 snd_fm801 0000:0d:01.0: detected TEA575x radio type SF64-PCR
 snd_fm801 0000:0d:01.0: AC'97 interface is busy (1)
 snd_fm801 0000:0d:01.0: AC'97 interface is busy (1)
...
 snd_fm801 0000:0d:01.0: AC'97 0 does not respond - RESET
 snd_fm801 0000:0d:01.0: AC'97 interface is busy (1)
 snd_fm801 0000:0d:01.0: AC'97 interface is busy (1)
 snd_fm801 0000:0d:01.0: AC'97 0 access is not valid [0x0], removing mixer.
 snd_fm801: probe of 0000:0d:01.0 failed with error -5

Do a copy of TUNER_ONLY bit to be applied after autodetection is done.

Fixes: d7ba858a (ALSA: fm801: implement TEA575x tuner autodetection)
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>