muge: configure LEDs per dtb (for Raspberry Pi 3B+)

Also apply some style(9) and remove the message about EEPROM configuration
(if there's an EEPROM the hardware handles LED configuration itself).

PR: 237325
Reviewed by: ian
MFC after: 2 weeks
Submitted by: Ralf <iz-rpi03@hs-karlsruhe.de>