ipa-server-install uninstall: remove tdb files
    
    ipa-server-install uninstaller must remove samba *.tdb files
    in /var/lib/samba, /var/lib/samba/private and /var/lib/samba/lock.
    The current code calls rm on the relative path filename
    instead of building an absolute path filename,
    resulting in failure to remove the tdb files.
    
    Related: https://pagure.io/freeipa/issue/8687
    Signed-off-by: Florence Blanc-Renaud <flo@redhat.com>
    Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>