As local timer interrupts are now handled as normal interrupts,
remove the special case in the GIC handler.

Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Sascha Hauer <kernel@pengutronix.de>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Tested-and-Acked-by: NShawn Guo <shawn.guo@linaro.org>

This is a plain translation of assembly gic irq handler to C function
for CONFIG_MULTI_IRQ_HANDLER support on imx family.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>