irqchip/gic-v3: Switch high priority PPIs over to handle_percpu_devid_irq()

irqchip/gic-v3: Switch high priority PPIs over to handle_percpu_devid_irq()

It so appears that handle_percpu_devid_irq() is extremely similar to
handle_percpu_devid_fasteoi_nmi(), and that the differences do no justify
the horrid machinery in the GICv3 driver to handle the flow handler switch.

Stick with the standard flow handler, even for NMIs.

Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Will Deacon <will@kernel.org>
Link: https://patch.msgid.link/20251020122944.3074811-11-maz@kernel.org