* Xtensa Interrupt Distributor and Programmable Interrupt Controller (MX)

Required properties:
- compatible: Should be "cdns,xtensa-mx".

Remaining properties have exact same meaning as in Xtensa PIC
(see cdns,xtensa-pic.txt).

Examples:
	pic: pic {
		compatible = "cdns,xtensa-mx";
		/* one cell: internal irq number,
		 * two cells: second cell == 0: internal irq number
		 *            second cell == 1: external irq number
		 */
		#interrupt-cells = <2>;
		interrupt-controller;
	};