fdo#72727: Revert "-Werror=unused-but-set-variable second try"

This reverts commit ccf7b15c0a5776c6431fdcb0c0e2b0f3935ae3dc.
(cherry picked from commit 61d958f37ed2aad6be2eab7bb507e0fb77716eec)

Change-Id: I3fbb037200d3df0e392b66bdd0c9cafc573e1a57
Reviewed-on: https://gerrit.libreoffice.org/9659
Tested-by: Markus Mohrhard <markus.mohrhard@googlemail.com>
Reviewed-by: Markus Mohrhard <markus.mohrhard@googlemail.com>