V4L/DVB (8726): link tuner before saa7134

If saa7134_init is run before v4l2_i2c_drv_init (tuner), then
saa7134_board_init2 will try to set the tuner type for devices that don't
exist yet.  This moves tuner to before all of the device-specific drivers
so that it's loaded early enough on boot.

Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>