The synchronized service reload protocol added in systemd version 253
requires that the service provides a MONOTONIC_USEC field alongside the
RELOADING=1 notification message for synchronization purposes. The value
carried in this field must be the system CLOCK_MONOTONIC timestamp at
the time the notification message was generated as systemd compares it
to other CLOCK_MONOTONIC timestamps taken by pid1.
Signed-off-by: Ekaterina Lebedeva <ekaterina.lebedeva@yadro.com>