[oneshot-root] Don't rerun oneshot on dsme restart. JB#18250

There is no need to have "Requires=dsme.service" as it only makes oneshot-root to be rerun any time dsme is restarted. We want oneshot to be run once per boot, no more, no less.

Signed-off-by: Pekka Lundstrom <pekka.lundstrom@jollamobile.com>