irqchip: mips-gic: Let the core set struct irq_common_data affinity

gic_set_affinity() manually copies the provided cpumask to the struct
irq_common_data affinity field, returning IRQ_SET_MASK_OK_NOCOPY in
order to prevent the core code from doing that.

We can instead simply let the core code do it for us, by returning
IRQ_SET_MASK_OK instead of IRQ_SET_MASK_OK_NOCOPY & doing the copy
ourselves.

[ralf@linux-mips.org: Resolve merge conflict.]

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17056/


Signed-off-by: Ralf Baechle <ralf@linux-mips.org>