[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/mach-omap1/fpga.c

@@ -102,7 +102,7 @@ void innovator_fpga_IRQ_demux(unsigned int irq, struct irqdesc *desc,
 	     fpga_irq++, stat >>= 1) {
 		if (stat & 1) {
 			d = irq_desc + fpga_irq;
-			d->handle(fpga_irq, d, regs);
+			desc_handle_irq(fpga_irq, d, regs);
 		}
 	}
 }