RB1 wlan0 MAC addresses are not stable

[basak-qcom]

On RB1, the Debian image has a different MAC address against wlan0 on every boot. This is a pain for developers because it means that the IP address acquired does not remain stable in a regular DHCP environment.

Proposed solution: for a better developer experience, we should make sure that the MAC is consistent out of the box. In the worst case, we could do this in userspace on boot.

[b49020]

@loicpoulain has a U-Boot patch for this MAC address to be retrieved from eMMC boot0 partition, let me sync up with him to merge that in my U-Boot repo and also provide a way for MAC address provisioning for users.