ARM: vGIC: rework gic_remove_from_queues()

ARM: vGIC: rework gic_remove_from_queues()

The function name gic_remove_from_queues() was a bit of a misnomer,
since it just removes an IRQ from the pending queue, not both queues.
Rename the function to make this more clear, also give it a pointer to
a struct pending_irq directly and rely on the VGIC VCPU lock to be
already taken, so this can be used in more places. This results in the
lock to be taken in the caller instead now.
Replace the list removal in gic_clear_pending_irqs() with a call to
this function.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Julien Grall <julien.grall@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>