INVITES with proxy auth were sent with a different branch

than what was in the invite_branch of a sip_pvt, meaning
that if a CANCEL were sent later, the branch in the CANCEL
would not match the branch in the latest INVITE sent out, leading
to some endpoints responding to the CANCEL with a 481.

(closes issue #13714)
Reported by: fnordian
Patches:
      invite_branch.patch uploaded by fnordian (license 110)



git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@150207 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -8004,7 +8004,7 @@ static int reqprep(struct sip_request *req, struct sip_pvt *p, int sipmethod, in
 		seqno = p->ocseq;
 	}
 	
-	if (sipmethod == SIP_CANCEL) {
+	if (sipmethod == SIP_CANCEL || sipmethod == SIP_INVITE) {
 		p->branch = p->invite_branch;
 		build_via(p);
 	} else if (newbranch) {