This patch adds a new IEEE802154_HW_ARET hardware flag for indicating
that the transceiver supports ARET handling. Also remove the
IEEE802154_HW_FRAME_RETRIES from IEEE802154_HW_CSMA flag. Frame retries
handling is part of ARET.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>