[media] bttv: Add noname Bt848 capture card with 14MHz xtal

Add support for noname Bt848 capture-only card (3x composite, 1x S-VHS)
with 14MHz crystal:
http://www.rainbow-software.org/images/hardware/bt848_.jpg


14MHz PLL was not supported by bttv driver until now.

[mchehab@redhat.com: CodingStyle fixes]
Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>