Skip `-Wl,--version-script` on libclang_rt.* stubs (temp hack)

The checked-in libclang_rt.* prebuilts do not contain versioned symbols,
but the autogenerated map.txt file for these libraries contain versions
e.g.
LIBCLANG_RT_ASAN {
  global:
...
}
```

This causes a discrepancy between the symbols in the stubs and impl
variants of these libraries. After https://r.android.com/3236596 is
submitted and a new set of libclang_rt.* prebuilts are generated, this
discrepancy will go away.

For now, skip `-Wl,version-script` when generating the stub
variants of these libraries to prevent link errors at build time.

Test: lunch aosp_panther_hwasan-trunk_staging-userdebug && m crash_dump
Bug: 3222365
Change-Id: Ic1e06cb58ec33b761136ac325f191da7ac900151