[SPARC/64] constify of_get_property return: drivers

The only unfortunate bit here is that the name field of struct map_info
is not const, so for now we put a cast on the assignment of it.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/serial/sunsu.c b/drivers/serial/sunsu.c
index 96a852a..bfd4417 100644
--- a/drivers/serial/sunsu.c
+++ b/drivers/serial/sunsu.c
@@ -1387,8 +1387,8 @@
 	struct device_node *ap = of_find_node_by_path("/aliases");
 
 	if (ap) {
-		char *keyb = of_get_property(ap, "keyboard", NULL);
-		char *ms = of_get_property(ap, "mouse", NULL);
+		const char *keyb = of_get_property(ap, "keyboard", NULL);
+		const char *ms = of_get_property(ap, "mouse", NULL);
 
 		if (keyb) {
 			if (dp == of_find_node_by_path(keyb))