gpiolib returns -ENXIO if struct gpio_chip::to_irq isn't set, so it's
safe to always call.
Based on PPC patch
"powerpc/gpio: support gpio_to_irq()"
78331aded9
Signed-off-by: Michal Simek <monstr@monstr.eu>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Acked-by: John Linn <john.linn@xilinx.com>
Acked-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Acked-by: John Williams <john.williams@petalogix.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>