The new property will allow to specify the range of GIC hwirqs to use for IPIs.

This is an optinal property. We preserve the previous behaviour of allocating
the last 2 * gic_vpes if it's not specified or DT is not supported.
Signed-off-by: Qais Yousef <qais.yousef@imgtec.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: <jason@lakedaemon.net>
Cc: <marc.zyngier@arm.com>
Cc: <jiang.liu@linux.intel.com>
Cc: <linux-mips@linux-mips.org>
Cc: <lisa.parratt@imgtec.com>
Cc: Qais Yousef <qsyousef@gmail.com>
Link: http://lkml.kernel.org/r/1449580830-23652-20-git-send-email-qais.yousef@imgtec.comSigned-off-by: Thomas Gleixner <tglx@linutronix.de>