[SPARC64] constify of_get_property return: include

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/asm-sparc64/parport.h b/include/asm-sparc64/parport.h
index 284dfd0..6340a52 100644
--- a/include/asm-sparc64/parport.h
+++ b/include/asm-sparc64/parport.h
@@ -103,7 +103,7 @@
 	if (!strcmp(edev->prom_node->name, "ecpp"))
 		return 1;
 	if (!strcmp(edev->prom_node->name, "parallel")) {
-		char *compat;
+		const char *compat;
 
 		compat = of_get_property(edev->prom_node,
 					 "compatible", NULL);