irqchip: Add RZ/V2H(P) Interrupt Control Unit (ICU) driver

Add driver for the Renesas RZ/V2H(P) Interrupt Control Unit (ICU).

This driver supports the external interrupts NMI, IRQn, and TINTn.

Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20241009230817.798582-3-fabrizio.castro.jz@renesas.com