ARM: mxs: icoll: Fix sparse warning

Fix the following sparse warning:

arch/arm/mach-mxs/icoll.c:103:13: warning: symbol 'icoll_of_init' was not declared. Should it be static?

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
diff --git a/arch/arm/mach-mxs/icoll.c b/arch/arm/mach-mxs/icoll.c
index 8fb23af..e26eeba 100644
--- a/arch/arm/mach-mxs/icoll.c
+++ b/arch/arm/mach-mxs/icoll.c
@@ -100,7 +100,7 @@
 	.xlate = irq_domain_xlate_onecell,
 };
 
-void __init icoll_of_init(struct device_node *np,
+static void __init icoll_of_init(struct device_node *np,
 			  struct device_node *interrupt_parent)
 {
 	/*