linux-phytec-ti

irqchip/i8259: Prepare i8259_irq_dispatch for irq argument removal

Make irq a local variable and retrieve domain from the irq descriptor
which avoid a redundant lookup.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ralf Baechle <ralf@linux-mips.org>