arm64: allwinner: h5: fix pinctrl IRQs

The pin controller of H5 has three IRQs at the chip's GIC, which
represents three banks of pinctrl IRQs. However, the device tree used to
miss the third IRQ of the pin controller, which makes the PG bank IRQ
not usable.

Add the missing IRQ to the pinctrl node.

Fixes: 4e36de17

 ("arm64: allwinner: h5: add Allwinner H5 .dtsi")
Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>