irqchip/mips-gic: Map to VPs using HW VPNum

When mapping an interrupt to a VP(E) we must use the identifier for the
VP that the hardware expects, and this does not always match up with the
Linux CPU number. Commit d46812bb ("irqchip: mips-gic: Use HW IDs
for VPE_OTHER_ADDR") corrected this for the cases that existed at the
time it was written, but commit 2af70a96 ("irqchip/mips-gic: Add a
IPI hierarchy domain") added another case before the former patch was
merged. This leads to incorrectly using Linux CPU numbers when mapping
interrupts to VPs, which breaks on certain systems such as those with
multi-core I6400 CPUs. Fix by adding the appropriate call to
mips_cm_vp_id() to retrieve the expected VP identifier.

Fixes: d46812bb ("irqchip: mips-gic: Use HW IDs for VPE_OTHER_ADDR")
Fixes: 2af70a96 ("irqchip/mips-gic: Add a IPI hierarchy domain")
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Qais Yousef <qsyousef@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20160705132600.27730-1-paul.burton@imgtec.com


Signed-off-by: Thomas Gleixner <tglx@linutronix.de>