chan_sip: Unref outbound proxy structure on dialog/pvt destruction.

Make sure outbound proxy refs are always unreffed on dialog destruction.

Review: https://reviewboard.asterisk.org/r/4016/
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Merged revisions 423800 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Merged revisions 423801 from http://svn.asterisk.org/svn/asterisk/branches/11
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Merged revisions 423802 from http://svn.asterisk.org/svn/asterisk/branches/12


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/13@423803 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -4390,7 +4390,7 @@ int __sip_ack(struct sip_pvt *p, uint32_t seqno, int resp, int sipmethod)
 	  If obforcing is set, we will keep the outbound proxy during the whole
 	  dialog, regardless of what the SIP rfc says
 	*/
-	if (p->outboundproxy && !p->outboundproxy->force){
+	if (p->outboundproxy && !p->outboundproxy->force) {
 		ref_proxy(p, NULL);
 	}
 
@@ -6454,6 +6454,10 @@ void __sip_destroy(struct sip_pvt *p, int lockowner, int lockdialoglist)
 		p->options = NULL;
 	}
 
+	if (p->outboundproxy) {
+		ref_proxy(p, NULL);
+	}
+
 	if (p->notify) {
 		ast_variables_destroy(p->notify->headers);
 		ast_free(p->notify->content);