[media] dw2102: combine su3000_state and s6x0_state into dw2102_state

Two separate state structs are defined for different devices inside the
dw2102. Combine them, as both only contain one element.

This will also make it easier to further cleanup the driver.

Signed-off-by: Olli Salonen <olli.salonen@iki.fi>
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>