irqchip/renesas-rzv2h: Handle ICU error IRQ and add SWPE trigger

irqchip/renesas-rzv2h: Handle ICU error IRQ and add SWPE trigger

Handle the RZ/V2H ICU error interrupt to help diagnose latched bus,
ECC RAM, and CA55/IP error conditions.

Support error injection via ICU_SWPE to allow testing the pseudo error
error interrupts.

Account for SoC differences in ECC RAM error register coverage so the
handler only iterates over valid ECC status/clear banks, and route the
RZ/V2N compatible to a probe path with the correct ECC range while
keeping the existing RZ/V2H and RZ/G3E handling.

[ tglx: Convert to hwirq_within() and upgrade to pr_warn() for those errors ]

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260304113317.129339-8-prabhakar.mahadev-lad.rj@bp.renesas.com