[POWERPC] sound: 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 sound driver changes.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/sound/ppc/tumbler.c b/sound/ppc/tumbler.c
index 692c611..b94ecd0 100644
--- a/sound/ppc/tumbler.c
+++ b/sound/ppc/tumbler.c
@@ -1035,7 +1035,7 @@
 		return NULL;
   
 	for (np = np->child; np; np = np->sibling) {
-		char *property = get_property(np, "audio-gpio", NULL);
+		const char *property = get_property(np, "audio-gpio", NULL);
 		if (property && strcmp(property, name) == 0)
 			return np;
 	}  
@@ -1062,7 +1062,8 @@
 				struct pmac_gpio *gp, int is_compatible)
 {
 	struct device_node *node;
-	u32 *base, addr;
+	const u32 *base;
+	u32 addr;
 
 	if (is_compatible)
 		node = find_compatible_audio_device(device);
@@ -1074,9 +1075,9 @@
 		return -ENODEV;
 	}
 
-	base = (u32 *)get_property(node, "AAPL,address", NULL);
+	base = get_property(node, "AAPL,address", NULL);
 	if (! base) {
-		base = (u32 *)get_property(node, "reg", NULL);
+		base = get_property(node, "reg", NULL);
 		if (!base) {
 			DBG("(E) cannot find address for device %s !\n", device);
 			snd_printd("cannot find address for device %s\n", device);
@@ -1090,13 +1091,13 @@
 
 	gp->addr = addr & 0x0000ffff;
 	/* Try to find the active state, default to 0 ! */
-	base = (u32 *)get_property(node, "audio-gpio-active-state", NULL);
+	base = get_property(node, "audio-gpio-active-state", NULL);
 	if (base) {
 		gp->active_state = *base;
 		gp->active_val = (*base) ? 0x5 : 0x4;
 		gp->inactive_val = (*base) ? 0x4 : 0x5;
 	} else {
-		u32 *prop = NULL;
+		const u32 *prop = NULL;
 		gp->active_state = 0;
 		gp->active_val = 0x4;
 		gp->inactive_val = 0x5;
@@ -1105,7 +1106,7 @@
 		 * as we don't yet have an interpreter for these things
 		 */
 		if (platform)
-			prop = (u32 *)get_property(node, platform, NULL);
+			prop = get_property(node, platform, NULL);
 		if (prop) {
 			if (prop[3] == 0x9 && prop[4] == 0x9) {
 				gp->active_val = 0xd;