Remove germanisms in variables: sw/source/filter/ww1

Change-Id: Ieb61128a6497fc8f980b315a949ce74b2dc4adce
Reviewed-on: https://gerrit.libreoffice.org/8324
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>