of: Request and map make argument name constant

This patch makes the name argument from of_io_request_and_map constant.

Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
diff --git a/include/linux/of_address.h b/include/linux/of_address.h
index 8cb14eb..d88e81b 100644
--- a/include/linux/of_address.h
+++ b/include/linux/of_address.h
@@ -106,7 +106,7 @@
 				  struct resource *r);
 void __iomem *of_iomap(struct device_node *node, int index);
 void __iomem *of_io_request_and_map(struct device_node *device,
-					int index, char *name);
+					int index, const char *name);
 #else
 
 #include <linux/io.h>
@@ -123,7 +123,7 @@
 }
 
 static inline void __iomem *of_io_request_and_map(struct device_node *device,
-					int index, char *name)
+					int index, const char *name)
 {
 	return IOMEM_ERR_PTR(-EINVAL);
 }