MAC assignment based on vendor firmware:
2.4 GHz *:b4 (factory 0x04)
LAN/label *:b4 (factory 0x28)
WAN *:b5 (factory 0x2e)
The previously used location 0x4000 for ethernet is actually empty.
Therefore, fix the ethernet MAC address and set it as label-mac-address.
Fixes: 5ef79af4f8 ("ramips: add support for Ravpower WD03")
Suggested-by: Russell Morris <rmorris@rkmorris.us>
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>