irqchip: mips-gic: Don't treat FDC IRQ as percpu devid

Treat the Fast Debug Channel (FDC) interrupt the same as the timer and
performance counter interrupts. Like them, the FDC IRQ is also per-VPE,
and also doesn't use a per-CPU device ID yet. Per-CPU device IDs don't
seem to work with IRQF_SHARED which is needed for compatibility with
cores which don't route the FDC IRQ through the GIC. For hardware which
routes FDC IRQs through the GIC this is something that could be added
later.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9141/


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