fixes deadlock when performing directed pickup w Invite/replaces

(closes issue #15340)
Reported by: lmsteffan
Patches:
      deadlock.patch uploaded by lmsteffan (license 779)
Tested by: lmsteffan



git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@219371 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -20723,7 +20723,9 @@ static int handle_request_invite(struct sip_pvt *p, struct sip_request *req, int
 			do_magic_pickup(c, pickup.exten, pickup.context);
 
 			/* Now we're either masqueraded or we failed to pickup, in either case we... */
+			sip_pvt_unlock(p);
 			ast_hangup(c);
+			sip_pvt_lock(p);
 
 			return 0;
 		} else {