Fix compile error.

(issue ASTERISK-20724)
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Merged revisions 376864 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Merged revisions 376865 from http://svn.asterisk.org/svn/asterisk/branches/10


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/11@376866 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -17801,7 +17801,7 @@ static void check_via(struct sip_pvt *p, struct sip_request *req)
 		if (ast_sockaddr_resolve_first(&tmp, c, 0)) {
 			ast_log(LOG_WARNING, "Could not resolve socket address for '%s'\n", c);
 			port = STANDARD_SIP_PORT;
-		} else if (!(port = ast_sockaddr_port(&tmp)) {
+		} else if (!(port = ast_sockaddr_port(&tmp))) {
 			port = STANDARD_SIP_PORT;
 			ast_sockaddr_set_port(&tmp, port);
 		}