arm: Add export.h to ARM specific files as required.

These files all make use of one of the EXPORT_SYMBOL variants
or the THIS_MODULE macro.  So they will need <linux/export.h>

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/arch/arm/plat-iop/gpio.c b/arch/arm/plat-iop/gpio.c
index 640e498..e4de9be 100644
--- a/arch/arm/plat-iop/gpio.c
+++ b/arch/arm/plat-iop/gpio.c
@@ -15,6 +15,7 @@
 #include <linux/types.h>
 #include <linux/errno.h>
 #include <linux/gpio.h>
+#include <linux/export.h>
 #include <asm/hardware/iop3xx.h>
 
 void gpio_line_config(int line, int direction)