Add sectorization for VVHM FIR, modified airport data (#1072)

* Add sectorization for VVHM FIR, modified airport data

Added sector 1 to 7 for VVHM
Modified data for airport within VCL, removed non existed airport, added data for some airport within Viet Nam.

* Modified VVHM A B sector

Error in callsign has been fixed

* Minor fix for Mekong Radar name

* Removed all military airport from database due to national security

---------

Co-authored-by: Adrian Bjerke <[email protected]>

Author: AnTruongTV