Bluetooth: Mesh: Fix handling of app index and local device key

Fix problem of not checking if the remote device key is actually our
own. This bug was intruduced in
46a95f1 and causes failure of models
that use app_idx BT_MESH_KEY_DEV_REMOTE. Since this is used by cfg_cli,
it was not possible to do self-configuration.

Signed-off-by: Tobias Svehagen <[email protected]>

Author: tsvehagen

subsys/bluetooth/mesh/transport.c

@@ -1717,7 +1717,9 @@ int bt_mesh_app_key_get(const struct bt_mesh_subnet *subnet, u16_t app_idx,
 {
 	struct bt_mesh_app_key *app_key;
 
-	if (app_idx == BT_MESH_KEY_DEV_LOCAL) {
+	if (app_idx == BT_MESH_KEY_DEV_LOCAL ||
+	    (app_idx == BT_MESH_KEY_DEV_REMOTE &&
+	     bt_mesh_elem_find(addr) != NULL)) {
 		*aid = 0;
 		*key = bt_mesh.dev_key;
 		return 0;