Pass a pointer to the i2c bus to the pll callbacks (stv0299 only).

It was not possible to tell which i2c bus should be used if an adapter has
multiple frontends on multiple i2c buses.
Signed-off-by: Andreas Oberritter <obi@linuxtv.org>
Signed-off-by: Johannes Stezenbach <js@linuxtv.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>