mips: lantiq: Add missing of_node_put() in irq.c

In icu_of_init(), of_find_compatible_node() will return a node
pointer with refcount incremented. We should use of_node_put()
when it is not used anymore.
Signed-off-by: Liang He <windhl@126.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/lantiq/irq.c

@@ -408,6 +408,7 @@ int __init icu_of_init(struct device_node *node, struct device_node *parent)
 		if (!ltq_eiu_membase)
 			panic("Failed to remap eiu memory");
 	}
+	of_node_put(eiu_node);
 
 	return 0;
 }