Fix ambiguous grammar for devicetree rule

Commit 737b2df3, "overlay: Add syntactic sugar version of overlays"
introduced an empty rule for "devicetree" that created ambiguities in
the grammar and causes the following warning:

         BISON dtc-parser.tab.c
  dtc-parser.y: warning: 3 shift/reduce conflicts [-Wconflicts-sr]

Fix the grammar by explicitly testing for the condition the
new overlay grammar wants to use. This means duplicating a very small
amount of grammar processing code, but the alternative seems to be a
more invasive reorganization of the devicetree rule. Better to fix it
this way now and save the reorg for a separate patch.

Signed-off-by: Grant Likely <grant.likely@arm.com>
Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 2 insertions, 1 deletions

diff --git a/livetree.c b/livetree.c
index 457d01e..57b7db2 100644
--- a/livetree.c
+++ b/livetree.c
@@ -216,7 +216,7 @@ struct node *merge_nodes(struct node *old_node, struct node *new_node)
 	return old_node;
 }
 
-void add_orphan_node(struct node *dt, struct node *new_node, char *ref)
+struct node * add_orphan_node(struct node *dt, struct node *new_node, char *ref)
 {
 	static unsigned int next_orphan_fragment = 0;
 	struct node *node;
@@ -236,6 +236,7 @@ void add_orphan_node(struct node *dt, struct node *new_node, char *ref)
 	name_node(node, name);
 
 	add_child(dt, node);
+	return dt;
 }
 
 struct node *chain_node(struct node *first, struct node *list)