Bridging: Fix orphaned bridge if neither of the joining channels can join.

The original issue noted that the bridge is orphaned when res_parking.so
is not loaded and a call uses the dial kK flags.

A similar issue happens when only one of the park flags is used.  In this
case you have the bridge with one or the other channel left in it.  The
channel and bridge will stay around until the channel hangs up.

* Fixed the initial bridge channel push failure to act as if the channel
were kicked out of the bridge.  The bridge then decides if it needs to be
dissolved.

(closes issue ASTERISK-22629)
Reported by: Kevin Harwell

Review: https://reviewboard.asterisk.org/r/2928/


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/12@401424 65c4cc65-6c06-0410-ace0-fbb531ad65f3

include/asterisk/bridge_channel_internal.h

@@ -107,6 +107,9 @@ void bridge_channel_settle_owed_events(struct ast_bridge *orig_bridge, struct as
  *
  * \retval 0 on success.
  * \retval -1 on failure.  The channel did not get pushed.
+ *
+ * \note On failure the caller must call
+ * ast_bridge_features_remove(bridge_channel->features, AST_BRIDGE_HOOK_REMOVE_ON_PULL);
  */
 int bridge_channel_internal_push(struct ast_bridge_channel *bridge_channel);