dt-bindings: interrupt-controller: Convert snps,archs-idu-intc to DT schema

Convert the ARC-HS Interrupt Distribution Unit interrupt controller
binding to schema format. It's a straight-forward conversion of the
typical interrupt controller.

Link: https://lore.kernel.org/r/20250505144830.1292495-1-robh@kernel.org


Signed-off-by: Rob Herring (Arm) <robh@kernel.org>