This commit prioritizes usec timer over msec. Doing so improves
CSL by helping scheduling timeslots on IEEE 802.15.4 with lower miss
rate.
Signed-off-by: Przemyslaw Bida <przemyslaw.bida@nordicsemi.no>
Move OpenThread's glue code along with the Kconfig files that configure
OpenThread stack itself into module directory.
Update the maintainers file to reflect this change.
Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>