i2c-pnx.c: Use resources in platforms

As a precondition for device tree conversion, the platforms using i2c-pnx.c are
converted to using mem and irq resources instead of platform data.

Signed-off-by: Roland Stigge <stigge@antcom.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>