[ARM] 5605/1: Fix ep93xx gpio.c headers

Fix a number of build errors in ep93xx gpio.c due to to missing irq.h
Signed-off-by: Ryan Mallon <ryan@bluewatersys.com>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-ep93xx/gpio.c

@@ -18,6 +18,7 @@
 #include <linux/seq_file.h>
 #include <linux/io.h>
 #include <linux/gpio.h>
+#include <linux/irq.h>
 
 #include <mach/hardware.h>