multiple attributes of the same name on the same element,
because AttributeList was wrongly re-used

Change-Id: I29b2317ce3d836d7349fa0474709726bed2c5ad4
Reviewed-on: https://gerrit.libreoffice.org/51087Reviewed-by: Thorsten Behrens <Thorsten.Behrens@CIB.de>
Tested-by: Thorsten Behrens <Thorsten.Behrens@CIB.de>