[PATCH] ppc64: fix use kref for device_node refcounting (fix)

The recent ppc64 patch to use kref for device_node refcounting
introduced an unbalanced get/put in of_add_node which would cause
newly-added device nodes to be prematurely freed.  Sorry for the
screwup, a more rigorously tested fix follows.
Signed-off-by: Nathan Lynch <nathanl@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/ppc64/kernel/prom.c

@@ -1771,6 +1771,7 @@ int of_add_node(const char *path, struct property *proplist)
 	np->properties = proplist;
 	OF_MARK_DYNAMIC(np);
 	kref_init(&np->kref);
+	of_node_get(np);
 	np->parent = derive_parent(path);
 	if (!np->parent) {
 		kfree(np);