irqchip: mips-gic: Remove gic_set_dual_edge()

Remove the gic_set_dual_edge() function in favour of using the new
change_gic_dual() accessor function which provides equivalent
functionality. This also allows us to remove the gic_update_bits()
function which gic_set_dual_edge() was the last user of, along with the
GIC_INTR_OFS() & GIC_INTR_BIT() macros.

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/17031/


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