MIPS, IRQ: Use irq_desc_get_xxx() to avoid redundant lookup of irq_desc

MIPS, IRQ: Use irq_desc_get_xxx() to avoid redundant lookup of irq_desc

Use irq_desc_get_xxx() to avoid redundant lookup of irq_desc while we
already have a pointer to corresponding irq_desc.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Acked-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Aleksey Makarov <aleksey.makarov@auriga.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86@kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Cc: linux-acpi@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10086/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>