KCM: Queue requests by the same UID
In order to avoid race conditions, we queue requests towards the KCM
responder coming from the same client UID.
Reviewed-by: Michal Židek <mzidek@redhat.com>
Reviewed-by: Simo Sorce <simo@redhat.com>
Reviewed-by: Lukáš Slebodník <lslebodn@redhat.com>