rb5: Set Ethernet MAC address on boot am: a961f043ae am: 9fd963eefd am: 8eac097255 am: b7c3d561ff am: cd2a32358d

Original change: https://android-review.googlesource.com/c/device/linaro/dragonboard/+/2737313

Change-Id: Ib1d2cc59c7fbdea29bd3420a86c241cb93633f72
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>