packaging: windows spec: Remove 'artifacts' from paths
packaging: windows spec: Remove 'artifacts' from paths

Change all /usr/share/artifacts to /usr/share.

See:

https://gerrit.ovirt.org/47771 - spice-nsis aka ovirt-wgt
https://gerrit.ovirt.org/47460 - ovirt-wgt-toolchain
https://gerrit.ovirt.org/47461 - ovirt-guest-agent

Change-Id: Ia95c93d7399758fe4ae6bbf22219065b7a58c4ae
Signed-off-by: Yedidyah Bar David <e7f2f616ce8817ad893bbeaad3e942e94c69d323@redhat.com>
oVirt/ovirt-guest-agent,oVirt/ovirt-guest-agent,oVirt/ovirt-guest-agent,oVirt/ovirt-guest-agent