Libhtp request: extra whitespace interpreted as dummy new request
Reported in https://github.com/OISF/libhtp/pull/290
In htp_connp_REQ_FINALIZE, we unread the last end of line so that subsequent calls to htp_connp_REQ_LINE work. However, whenever we enter htp_connp_REQ_IDLE state, the check IN_TEST_NEXT_BYTE_OR_RETURN(connp) always passes even when there is no more data beyond the CRLF creating an empty transaction. htp_connp_REQ_IDLE now explicitly checks to make sure that if we only have two bytes of data, those two bytes are not simply the CRLF before starting a new transaction.