Free any datastores attached to dummy channels.

Revision 370205 added the use of a datastore attached to a dummy channel to
resolve a memory leak, but ast_dummy_channel_destructor() in this branch did
not free datastores, resulting in a continued (but slightly smaller) memory
leak. This patch backports the change to free said datastores from the Asterisk
trunk.

(related to issue AST-916)
........

Merged revisions 370360 from http://svn.asterisk.org/svn/asterisk/branches/1.8


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/10@370361 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/channel.c

@@ -2527,6 +2527,13 @@ static void ast_dummy_channel_destructor(void *obj)
 	struct ast_channel *chan = obj;
 	struct ast_var_t *vardata;
 	struct varshead *headp;
+	struct ast_datastore *datastore;
+
+	/* Get rid of each of the data stores on the channel */
+	while ((datastore = AST_LIST_REMOVE_HEAD(&chan->datastores, entry))) {
+		/* Free the data store */
+		ast_datastore_free(datastore);
+	}
 
 	headp = &chan->varshead;