Add support for the analog functionality found in the au0828 bridge

Thanks to Michael Krufky <mkrufky@linuxtv.org> and Steven Toth
<stoth@linuxtv.org> for providing sample hardware, engineering level support,
and testing.
Signed-off-by: Devin Heitmueller <dheitmueller@linuxtv.org>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
[mchehab@redhat.com: fix compilation by adding linux/version.h]
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>