gpio: omap: Remove unneeded include

The <linux/irqchip/chained_irq.h> header is already included
when selecting GPIOLIB_IRQCHIP so there is no need to do it
in the driver. This is a left over from commit fb655f5
("gpio: omap: convert driver to use gpiolib irqchip").
Signed-off-by: Javier Martinez Canillas <jmartinez@softcrates.net>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-omap.c

@@ -24,7 +24,6 @@
 #include <linux/pm.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
-#include <linux/irqchip/chained_irq.h>
 #include <linux/gpio.h>
 #include <linux/bitops.h>
 #include <linux/platform_data/gpio-omap.h>