Initialize ast_sockaddr before calling ast_sockaddr_resolve

Avoid possible jump based on unitialized value
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Merged revisions 340715 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Merged revisions 340716 from http://svn.asterisk.org/svn/asterisk/branches/10


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@340719 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -15685,7 +15685,7 @@ static void check_via(struct sip_pvt *p, struct sip_request *req)
 {
 	char via[512];
 	char *c, *maddr;
-	struct ast_sockaddr tmp;
+	struct ast_sockaddr tmp = { { 0, } };
 	uint16_t port;
 
 	ast_copy_string(via, sip_get_header(req, "Via"), sizeof(via));