fdo#39440 reduce scope of local variables

This addresses some cppcheck warnings.

Change-Id: I8931ff46394923d672e08b3a5c9ab75bb6ffb0a9
Reviewed-on: https://gerrit.libreoffice.org/13385
Reviewed-by: Markus Mohrhard <markus.mohrhard@googlemail.com>
Tested-by: Markus Mohrhard <markus.mohrhard@googlemail.com>