fix build

Change-Id: I65476b98a58b749619003965c41cfe0f32ae2e13
(cherry picked from commit 477e26b9ab681460823f7af042713e28f043cacb)
Reviewed-on: https://gerrit.libreoffice.org/7996
Reviewed-by: Fridrich Strba <fridrich@documentfoundation.org>
Tested-by: Fridrich Strba <fridrich@documentfoundation.org>