qosmngr : standard Linux support via tc+iptables

REQUIREMENT: Implementation of unified standard linux interface for applying qos configuration on Mediatek board. DESIGN CONSIDERATION: Use of standard linux interfaces tc+iptables IMPLEMENTATION: The existing /lib/qos/qos.sh has been leveraged to derive the parameters, required for tc commands from the "/etc/config/qos" uci file and vendor specific tmctl commands eliminated with linux tc commands. The framework to compile and install qosmngr package on Mediatek Panther (mt7986) box has been made to work.

The change set involves two different branches. One is in "iopsys-mediatek" and the other in "iopsys".