[tz] About Asia/Hanoi

[Meno Hochschild]

Should there be a link between Asia/Hanoi and Asia/Ho_Chi_Minh in TZDB?

Background of my question is an issue reported on the 
ThreetenBP-issue-tracker (see: 
https://github.com/ThreeTen/threetenbp/issues/57) where someone has 
observed a crash on its Android mobile phone using Asia/Hanoi as system 
tz (resided in OS) while the extra tz-distribution of an external 
library (ThreetenBP) does not contain that identifier (probably because 
it is in the backzone-file of TZDB).

With best regards

Meno