ARM: SAMSUNG: use static declaration when it is not used in other files

Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
diff --git a/arch/arm/plat-s5p/irq-gpioint.c b/arch/arm/plat-s5p/irq-gpioint.c
index 1fdfaa4..82c7311 100644
--- a/arch/arm/plat-s5p/irq-gpioint.c
+++ b/arch/arm/plat-s5p/irq-gpioint.c
@@ -41,7 +41,7 @@
 	void			(*handler)(unsigned int, struct irq_desc *);
 };
 
-LIST_HEAD(banks);
+static LIST_HEAD(banks);
 
 static int s5p_gpioint_set_type(struct irq_data *d, unsigned int type)
 {