core: set msg->pid when building local sip_msg_t from buf

(cherry picked from commit b5f3a21d919f44f8842c2d85fb9447072b0f1889)
(cherry picked from commit 58261d83f454e9f3ad259532d35ca2ca150d2076)
(cherry picked from commit 92ac558f300829a060f3cfa5a50cb3bf5ca4d975)

src/core/msg_translator.c

@@ -3111,6 +3111,7 @@ int build_sip_msg_from_buf(struct sip_msg *msg, char *buf, int len,
 
 	memset(msg, 0, sizeof(sip_msg_t));
 	msg->id = id;
+	msg->pid = my_pid();
 	msg->buf = buf;
 	msg->len = len;
 	if (parse_msg(buf, len, msg)!=0) {