memory: hide min free option

Since its no longer in our kernel we won't need this
option for now.

Signed-off-by: Blechd0se <alex.christ@hotmail.de>
cpu: fix values with whitespaces won't stick

On some devices (like the Defy) whitespaces make problems when
executed via echo. Solving this with a regex which checks for
whitespaces at the end of the string and filters them if necessary.

Moreover disabling the overclocking preference if the device doesn't
support it.

Signed-off-by: Blechd0se <alex.christ@hotmail.de>