docs: Reverting SDK r21.0.1 and NDK r8d Release Notes due to release conflict
Revert of CL change-id: Ieefa651cb8f1d01170a915fe956a97fd6a52e696
Revert of CL change-id: Ifaaa6579df6cb180f515f2a5e71b2ac62a1671c3

Change-Id: I315da053238943a7f77cc30564904bbf0cefed62
5 files changed