Move kcheckrunning into startkde
Summary:
kcheckrunning is only used by startkde, it shouldn't be in the ksmserver
folder.
No code or behavioural changes, just tidying.
Reviewers: Plasma, broulik
Reviewed By: Plasma, broulik
Subscribers: broulik, plasma-devel
Tags: Plasma
Differential Revision: https://phabricator.kde.org/D15202