Add Librem 11 board.
Librem 11 uses coreboot graphics init, which is done with FSP GOP.
Set a custom keymap for the volume/power keys. Configure the volume
keys as up/down arrows (for navigation in fbwhiptail, and for shell
history in the Linux console). Configure the power key as Enter.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
