i2c-pxa2xx: Add PCI support for PXA I2C controller

The Sodaville I2C controller is almost the same as found on PXA2xx. The
difference:
- the register are at a different offset
- no slave support

The PCI probe code adds three platform devices which are probed then by
the platform code.
The X86 part also adds dummy clock defines because we don't have HW
clock support.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>