ARM: ux500: fix up the I2C devices

The I2C device registration on the different ux500 board was
buggy due to a switch to dynamically assigned I2C host
addresses. This I2C host is still there, but we have to add
the devices dynamically instead of using board data.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>