Remove version script hack for libclang_rt.* libs

https://r.android.com/3221926 introduced a hack to not use the map.txt
files as --version-script for libclang_rt libs. This hack was necessary
since the map.txt files did not contain the api annotations, and also
contained a bogus version.

The map.txt files in `clang-r536225` do not contain these issues
- https://r.android.com/3195596 added the api annotations
- https://r.android.com/3236596 removed the bogus version

We can drop this hack now.

Test: m nothing --no-skip-soong-tests
Test: presubmits
Bug: 362596450
Change-Id: Icc261784dd85302eba4de3e38665cec32bdb0bad