[201807][platform] Accton: As5712-54x. Fix sfputil and accton_util#2002

Merged

lguohan merged 2 commits intosonic-net:201807from roylee123:as5712_54x_fix_sfputil

Aug 30, 2018

+54-14

Commits on Aug 29, 2018

[platform] accton as5712-54x, fixed
roylee123
committed
[platform] accton as5712-54x. Fix util.py error about SFP/QSFP's tx_disable and present.
roylee123
committed