[ARM] netwinder: clean up GPIO naming

Netwinder was using gpio_xxx names which could clash with the GPIO
layer.  Add a 'nw_' prefix to ensure that these remain separate.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mach-footbridge/dc21285.c b/arch/arm/mach-footbridge/dc21285.c
index d4c1e52..1330860 100644
--- a/arch/arm/mach-footbridge/dc21285.c
+++ b/arch/arm/mach-footbridge/dc21285.c
@@ -17,6 +17,7 @@
 #include <linux/ioport.h>
 #include <linux/irq.h>
 #include <linux/io.h>
+#include <linux/spinlock.h>
 
 #include <asm/irq.h>
 #include <asm/system.h>