smb: call smb_cutime on the correct url to actually set mtime properly
Summary:
since the introduction of partial resume dstUrl would can be the .part url
whereas dstOrigUrl is the final destination url.
i.e.
we called smbc_utime on smb://foo/bar.part rather than smb://foo/bar
BUG: 356651
FIXED-IN: 19.12.3
Test Plan: moving file to smb retains mtime
Reviewers: ngraham
Reviewed By: ngraham
Subscribers: kde-frameworks-devel, kfm-devel
Tags: Dolphin, Frameworks
Differential Revision: https://phabricator.kde.org/D27351