legacy: drop options that are now forcibly enabled

legacy: drop options that are now forcibly enabled

As Thomas said:

> In this sort of situation, we generally don't add any legacy
> handling.  Indeed, since the feature is now mandatory... the
> default behavior will always be OK.

> People who could be annoyed are people who had this feature
> disabled... which is now always enabled. But the legacy handling
> will anyway not help those people.

Reported-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>