sig_analog: Fix broken three-way conferencing.

Three-way calling for analog lines is currently broken.
If party A is on a call with party B and initiates a
three-way call to party C, the behavior differs depending
on whether the call is conferenced prior to party C
answering. The post-answer case is correct. However,
if A flashes before C answers, then the next flash
disconnects B rather than C, which is incorrect.

This error occurs because the subs are not swapped
in the misbehaving case. This is because the flash
handler only swaps the subs if C has answered already,
which is wrong. To fix this, we swap the subs regardless
of whether C has answered or not when the call is
conferenced. This ensures that C is disconnected
on the next hook flash, rather than B as can happen
currently.

ASTERISK-30043 #close

Change-Id: I96c5bf6c9b7eb2636136b716c677c82c079b6f06

Author: InterLinked1

channels/sig_analog.c

@@ -3386,10 +3386,8 @@ static struct ast_frame *__analog_handle_event(struct analog_pvt *p, struct ast_
 						/* Put them in the threeway, and flip */
 						analog_set_inthreeway(p, ANALOG_SUB_THREEWAY, 1);
 						analog_set_inthreeway(p, ANALOG_SUB_REAL, 1);
-						if (ast_channel_state(ast) == AST_STATE_UP) {
-							analog_swap_subs(p, ANALOG_SUB_THREEWAY, ANALOG_SUB_REAL);
-							orig_3way_sub = ANALOG_SUB_REAL;
-						}
+						analog_swap_subs(p, ANALOG_SUB_THREEWAY, ANALOG_SUB_REAL);
+						orig_3way_sub = ANALOG_SUB_REAL;
 						ast_queue_unhold(p->subs[orig_3way_sub].owner);
 						analog_set_new_owner(p, p->subs[ANALOG_SUB_REAL].owner);
 					} else {