[media] cx231xx: fix Kconfig dependencies

ERROR: "cx2341x_mpeg_ctrls" [drivers/media/video/cx231xx/cx231xx.ko] undefined!
ERROR: "cx2341x_fill_defaults" [drivers/media/video/cx231xx/cx231xx.ko] undefined!
ERROR: "cx2341x_log_status" [drivers/media/video/cx231xx/cx231xx.ko] undefined!
ERROR: "cx2341x_ctrl_get_menu" [drivers/media/video/cx231xx/cx231xx.ko] undefined!
ERROR: "cx2341x_update" [drivers/media/video/cx231xx/cx231xx.ko] undefined!
ERROR: "cx2341x_ctrl_query" [drivers/media/video/cx231xx/cx231xx.ko] undefined!
ERROR: "cx2341x_ext_ctrls" [drivers/media/video/cx231xx/cx231xx.ko] undefined!

Acked-by: Sri Deevi <Srinivasa.Deevi@conexant.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>