[ARM] Convert asm/io.h to linux/io.h

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mach-at91/gpio.c b/arch/arm/mach-at91/gpio.c
index 8392d5b..93e0614 100644
--- a/arch/arm/mach-at91/gpio.c
+++ b/arch/arm/mach-at91/gpio.c
@@ -18,8 +18,8 @@
 #include <linux/kernel.h>
 #include <linux/list.h>
 #include <linux/module.h>
+#include <linux/io.h>
 
-#include <asm/io.h>
 #include <mach/hardware.h>
 #include <mach/at91_pio.h>
 #include <mach/gpio.h>