such as pull-up, multi drive, etc.
Required properties for iomux controller:
-- compatible: "atmel,at91rm9200-pinctrl"
+- compatible: "atmel,at91rm9200-pinctrl" or "atmel,at91sam9x5-pinctrl"
- atmel,mux-mask: array of mask (periph per bank) to describe if a pin can be
configured in this periph mode. All the periph and bank need to be describe.