fdo#80617 Simplification of status bar page numbering

Change-Id: I520f53e85cca8f23992c8deeaf14ff2f4fc9bb3d
Reviewed-on: https://gerrit.libreoffice.org/11117
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>