* CircleCI: readd librem_mini while making sure that if a board build fails, all logfile modified in the last minute are outputted on the CircleCI console prior to really failing and exiting
* librem_mini-NoTPM: addition of board config, distinctive coreboot config (required per Heads build system) to construct a ROM without TPM requirement.
* librem_mini: deletion of board and coreboot relative config, keeping librem_mini-NoTPM and coreboot config only. Removed librem_mini board build under CircleCI, keeping only librem_mini-NoTPM
