[kioslave/remote] Fix porting bugs
Summary:
Commit 72e39f083a10 broke the remote ioslave from Dolphin Details view
mode, because of missing slashes or otherwise broken QUrls.
BUG: 376131
FIXED-IN: 5.9.2
Test Plan: remote:/ now works again from Dolphin Details view mode.
Reviewers: Plasma
Subscribers: plasma-devel
Tags: Plasma
Differential Revision: https://phabricator.kde.org/D4480