Add a device node for the Interrupt Controller for External Devices
(INTC-EX) on R-Car M3-W, which serves external IRQ pins IRQ[0-5].
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>