[POWERPC] video & agp: Constify & voidify get_property()

Now that get_property() returns a void *, there's no need to cast its
return value. Also, treat the return value as const, so we can
constify get_property later.

powerpc-specific video & agp driver changes.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/drivers/video/nvidia/nv_of.c b/drivers/video/nvidia/nv_of.c
index 8209106..d9af88c 100644
--- a/drivers/video/nvidia/nv_of.c
+++ b/drivers/video/nvidia/nv_of.c
@@ -32,7 +32,7 @@
 {
 	struct nvidia_par *par = info->par;
 	struct device_node *parent, *dp;
-	unsigned char *pedid = NULL;
+	const unsigned char *pedid = NULL;
 	static char *propnames[] = {
 		"DFP,EDID", "LCD,EDID", "EDID", "EDID1",
 		"EDID,B", "EDID,A", NULL };
@@ -42,20 +42,19 @@
 	if (parent == NULL)
 		return -1;
 	if (par->twoHeads) {
-		char *pname;
+		const char *pname;
 		int len;
 
 		for (dp = NULL;
 		     (dp = of_get_next_child(parent, dp)) != NULL;) {
-			pname = (char *)get_property(dp, "name", NULL);
+			pname = get_property(dp, "name", NULL);
 			if (!pname)
 				continue;
 			len = strlen(pname);
 			if ((pname[len-1] == 'A' && conn == 1) ||
 			    (pname[len-1] == 'B' && conn == 2)) {
 				for (i = 0; propnames[i] != NULL; ++i) {
-					pedid = (unsigned char *)
-						get_property(dp, propnames[i],
+					pedid = get_property(dp, propnames[i],
 							     NULL);
 					if (pedid != NULL)
 						break;
@@ -67,8 +66,7 @@
 	}
 	if (pedid == NULL) {
 		for (i = 0; propnames[i] != NULL; ++i) {
-			pedid = (unsigned char *)
-				get_property(parent, propnames[i], NULL);
+			pedid = get_property(parent, propnames[i], NULL);
 			if (pedid != NULL)
 				break;
 		}