cx23885: Drop empty i2c algorithm control callback

i2c_algorithm.algo_control is about to be removed.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Reviewed-by: Michael Krufky <mkrufky@linuxtv.org>
Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org>