ieee802154: fix byteorder issues

This patch fix byteorder issues which occurs because we compare __le64
with an host byteorder value. Simple add a cpu_to_le64 to convert the
host byteorder values to __le64.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Reported-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>