[Mono.Android] Backfill map.csv API levels. (#4703)

In commit 91970b1 we updated `src/Mono.Android/map.csv` to a new
version that contains entries for all Java `int` fields and the API
level in which they were introduced.  However this file was generated
before commit 3f438e4, which greatly increased the accuracy of our
API level contents

Use the increased accuracy of 3f438e46to to fill in many lines which
previously did not have API level information (ApiLevel = 0).

This commit does not change anything shipped, it's just better
bookkeeping for more accurate enumification.

Author: jpobst