Revert "ARM: OMAP: Mask interrupts when disabling interrupts, v2"

This reverts commit 5461af5a.

Adding a disable hook to the irq_chip is not the way to fix the
problem being addressed by this patch.  Instead, we need to fix
support for [enable|disable]_irq_wake().
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>

arch/arm/mach-omap2/irq.c

@@ -134,7 +134,6 @@ static struct irq_chip omap_irq_chip = {
 	.ack	= omap_mask_ack_irq,
 	.mask	= omap_mask_irq,
 	.unmask	= omap_unmask_irq,
-	.disable = omap_mask_irq,
 };
 
 static void __init omap_irq_bank_init_one(struct omap_irq_bank *bank)