utils: eth_mac_addr: Fix the GSI/Treble compatibility am: e721f61fee

Original change: https://android-review.googlesource.com/c/device/linaro/dragonboard/+/2842354

Change-Id: I4d4c4fb87c7ab37c4d0c7f6f395dff4b19b32c74
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>