i2c: mediatek: Add arb clock in i2c driver

When two i2c controllers are internally connected to the same
GPIO pins, the arb clock is needed to ensure that the waveforms
do not interfere with each other. And we also need to enable
the interrupt to find arb lost, old i2c controllers also have
the bit.

Signed-off-by: Qii Wang <qii.wang@mediatek.com>
Reviewed-by: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>