Consolidate of_get_parent

This requires creating dummy of_node_{get,put} routines for sparc and
sparc64.  It also adds a read_lock around the parent accesses.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Paul Mackerras <paulus@samba.org>
Acked-by: David S. Miller <davem@davemloft.net>

arch/powerpc/kernel/prom.c

@@ -1240,27 +1240,6 @@ struct device_node *of_find_all_nodes(struct device_node *prev)
 }
 EXPORT_SYMBOL(of_find_all_nodes);
 
-/**
- *	of_get_parent - Get a node's parent if any
- *	@node:	Node to get parent
- *
- *	Returns a node pointer with refcount incremented, use
- *	of_node_put() on it when done.
- */
-struct device_node *of_get_parent(const struct device_node *node)
-{
-	struct device_node *np;
-
-	if (!node)
-		return NULL;
-
-	read_lock(&devtree_lock);
-	np = of_node_get(node->parent);
-	read_unlock(&devtree_lock);
-	return np;
-}
-EXPORT_SYMBOL(of_get_parent);
-
 /**
  *	of_get_next_child - Iterate a node childs
  *	@node:	parent node