pinctrl: renesas: rzt2h: Add GPIO IRQ chip to handle interrupts

pinctrl: renesas: rzt2h: Add GPIO IRQ chip to handle interrupts

The Renesas RZ/T2H (R9A09G077) and Renesas RZ/N2H (R9A09G087) SoCs have
IRQ-capable pins handled by the ICU, which forwards them to the GIC.

The ICU supports 16 IRQ lines, the pins map to these lines arbitrarily,
and the mapping is not configurable.

Add a GPIO IRQ chip to the pin controller that can be used to configure
these pins as IRQ lines.

The pin controller places the requested pins into IRQ function,
disabling GPIO mode. A hierarchical IRQ domain is used to forward other
functionality to the parent IRQ domain, the ICU. The ICU does level
translation and then forwards other functionality to the GIC.

Wakeup capability is implemented by placing the entire pin controller on
the wakeup path if any pins are requested to be wakeup-capable.

Signed-off-by: Cosmin Tanislav <cosmin-gabriel.tanislav.xa@renesas.com>
Reviewed-by: Linus Walleij <linusw@kernel.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260109143910.645628-2-cosmin-gabriel.tanislav.xa@renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>