Instead update them unconditionally as it is done with comments.

The data range has been set beforehand (considering the option
to include boundary columns with images only) so at this point
the swapping should happen unconditionally.

Follow-up for 3a2a430a

Change-Id: I1d75dd6e22db5cc28aa45f7b86dab013f3595199
Reviewed-on: https://gerrit.libreoffice.org/48383Reviewed-by: Samuel Mehrbrodt <Samuel.Mehrbrodt@cib.de>
Tested-by: Samuel Mehrbrodt <Samuel.Mehrbrodt@cib.de>