Board identifiers use them without underscore, too. Unify that.
Change-Id: I146384ef6dbe601ad131dada8224f43e6c18433d
Signed-off-by: Patrick Georgi <patrick@georgi-clan.de>
Reviewed-on: http://review.coreboot.org/674
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>