sun4i/sun7i combined cedarx driver

Modify sun4i cedarx driver to work on sun7i as well
Only tested a few video files on A10 and A20 Cubieboards

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
sun7i_defconfig: Build in i2c driver, otherwise the cpu voltage scaling won't work

Signed-off-by: Hans de Goede <hdegoede@redhat.com>