[ARM] Wrap calls to descriptor handlers

This is part of Thomas Gleixner's generic IRQ patch, which converts
ARM to use the generic IRQ subsystem.  Here, we wrap calls to
desc->handler() in an inline function, desc_handle_irq().  This
reduces the size of Thomas' patch since the changes become more
localised.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/plat-omap/gpio.c

@@ -590,7 +590,7 @@ static void gpio_irq_handler(unsigned int irq, struct irqdesc *desc,
 		if (!(isr & 1))
 			continue;
 		d = irq_desc + gpio_irq;
-		d->handle(gpio_irq, d, regs);
+		desc_handle_irq(gpio_irq, d, regs);
 	}
 }