Add a helper variable which contains the boardname separated from the
vendor name. It allows to switch to a device tree compatible string
based boardname, by keeping the $board:colour:function syntax in
scripts handling/adding config for LEDs.
Boards not using the device tree compatible string as based boardname
are unaffected by the change, since none of them uses a comma in the
boardname.
Signed-off-by: Mathias Kresin <dev@kresin.me>
ad002c397a