Revert^2 "Remove //apex_available:vendor" am: d7ba950097

Original change: https://android-review.googlesource.com/c/platform/external/armnn/+/3483056

Change-Id: I235506f1b64124d9cc3e33669de0c63869320936
Signed-off-by: Automerger Merge Worker <[email protected]>