Set min_sdk_version to be part of mainline modules

Modules contributing mainline modules (APK/APEX) should set
min_sdk_version as well as apex_available.

For now setting min_sdk_version doesn't change build outputs.
But build-time checks will be added soon.

Bug: 152655956
Bug: 178711289
Test: m
Change-Id: I17e44965c84ed5309aa0cba37095c2b71032c7f8
Merged-In: I17e44965c84ed5309aa0cba37095c2b71032c7f8