Fix handling of qdis without options

Some qdisc like htb want the parse_qopt to be called even if no options
present. Fixes regression caused by:

e9e78b0db0e023035e346ba67de838be851eb665 is the first bad commit
commit e9e78b0db0e023035e346ba67de838be851eb665
Author: Stephen Hemminger <stephen@networkplumber.org>
Date:   Mon Aug 26 08:41:19 2013 -0700

    tc: allow qdisc without options
htb: remove old unused duplicate qdisc name

Alexey had htb2 as name for version in ancient code.