The A83T has 3 I2C controllers under the standard bus. There is one
more in the R_ block section. The pin functions for the 3 controllers
are on PH 0~6. I2C2 can also be used on pins PE14 and PE15, but these
pins can also mux the CSI (camera sensor interface) controller's
embedded I2C controller. The latter seems to be preferred in the
reference designs for I2C camera sensor access, freeing I2C2 for other
uses.

This patch adds device nodes for the three standard I2C controllers,
as well as pinmux settings for the PH pins. For I2C0 and I2C1, since
they only have one possible setting, just set them by default.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>