[media] af9035: few small I2C master xfer changes

Biggest problem of that function is complexity. Try reduce complexity:

* define macros to detect all 3 supported xfers
* remove duplicate message maximum size checks

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