ARM: davinci: wrap HW interrupt numbers with a macro

Once we select SPARSE_IRQ, the interrupt numbers defined in mach/irqs.h
will only signify the hardware interrupt offsets, not the interrupt
numbers seen by linux. Introduce a wrapper macro that translates the
hwirq number to virtual numbers. For now it's just a dummy. Use that
macro when specifying the interrupts in resources for platform devices.

Reviewed-by: David Lechner <david@lechnology.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>