simplify build_android_gradle.sh (#25897)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/25897
It doesn't hurt to set all variables unconditionally.
And we can create link to lib directory instead of specific files - this
way it's easier to switch between dynamic/static library names.
Test Plan:
- check android gradle CI;
- use stack diff to check all 4 architectures on PR;
Pull Request resolved: https://github.com/pytorch/pytorch/pull/25897
Differential Revision: D17307240
Pulled By: ljk53
fbshipit-source-id: c975085ddda852ef7da1c29935c2f6a28d797e5a