[POWERPC] powermac: 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.

powermac platform & macintosh driver changes.

Built for pmac32_defconfig, g5_defconfig

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/drivers/macintosh/via-cuda.c b/drivers/macintosh/via-cuda.c
index 69d5452..7512d1c 100644
--- a/drivers/macintosh/via-cuda.c
+++ b/drivers/macintosh/via-cuda.c
@@ -123,7 +123,7 @@
 {
     struct adb_request req;
     phys_addr_t taddr;
-    u32 *reg;
+    const u32 *reg;
     int err;
 
     if (vias != 0)
@@ -132,7 +132,7 @@
     if (vias == 0)
 	return 0;
 
-    reg = (u32 *)get_property(vias, "reg", NULL);
+    reg = get_property(vias, "reg", NULL);
     if (reg == NULL) {
 	    printk(KERN_ERR "via-cuda: No \"reg\" property !\n");
 	    goto fail;