[media] dw2102: convert TechnoTrend S2-4600 to use I2C binding for demod

Convert the TT S2-4600 USB tuner to use the I2C binding for attaching
the demodulator instead of the old m88ds3103_attach method.

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