Remove unused Android.mk under device/google/felix am: 1890f3cb8b

Original change: https://android-review.googlesource.com/c/device/google/felix/+/2835912

Change-Id: Iad4487b4e81c72a8bb6893446448b10e679186a4
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>