definitions: Fix five languages' out-dated/missing BCP47 codes
- definitions: Fold duplicate Z1750 into Z1726/eml
- definitions: Fold duplicate Z1405 into Z1508/als
- definitions: Add BCP47 valid language codes as primary for Z1664/ro-cyrl-md
- definitions: Add BCP47 valid language codes as primary for Z1231/de-x-formal
- definitions: Swap primary and secondary language codes for Z1755/sgs
Bug: T360672
Bug: T360673
Bug: T360674
Bug: T360675
Bug: T360678