ARM: 7034/1: mach-u300: delete irq_to_gpio() function

This function is not used in the U300 build, and on the whole the
call is hard to consolidate so get rid of it from this machine.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-u300/include/mach/gpio.h

@@ -44,13 +44,4 @@ static inline unsigned gpio_to_irq(unsigned gpio)
 }
 #define gpio_to_irq gpio_to_irq
 
-static inline unsigned irq_to_gpio(unsigned irq)
-{
-	/*
-	 * FIXME: This is no 1-1 mapping at all, it points to the
-	 * whole block of 8 pins.
-	 */
-	return (irq - IRQ_U300_GPIO_PORT0) << 3;
-}
-
 #endif /* __MACH_U300_GPIO_H */