mac802154: cfg: remove test and set checks

mac802154: cfg: remove test and set checks

This patch removes several checks if a value is really changed. This
makes only sense if we have another layer call e.g. calling the
driver_ops which is done by callbacks like "set_channel".

For MAC settings which need to be set by phy registers (if the phy
supports that handling) this is set by doing an interface up currently
and are not direct driver_ops calls, so we remove the checks from these
configuration callbacks.

Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Suggested-by: Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>