Revert "Move libclang prebuilt to Android.bp"

This reverts commit f697cc615101adf28e36de45bc064d4356b8bc07.

Introducing a second prebuilt exposed a data race in Soong's prebuilt handling.

Change-Id: I2230289cfc473b69462a8d5ba0952d2e6caed838
2 files changed