AT91: Remove fixed mapping for AT91RM9200 ethernet

hi Jean-Christophe,

we need to pass the irq too as the hw ip does not belong to Atmel
so it can be attached to any irq

The IRQ is already passed via platform_resources.
The above patch also does:
   dev->irq = platform_get_irq(pdev, 0);


Regards,
  Andrew Victor