- Add the structure with already known fields offsets
(some of them were taken from this driver,
some (channel_plan, rf_* fields) - from TP-LINK official driver)
- Fix a typo / dehardcode a constant in RTL8192C ROM structure.
Tested with RTL8188EU, STA mode
Reviewed by: kevlo
Approved by: adrian (mentor)
Differential Revision: https://reviews.freebsd.org/D4274