cleanup already removed items from unusedcode.easy

Change-Id: I36648ef659e5d6a49ecd4874826bed009b5296e3
Reviewed-on: https://gerrit.libreoffice.org/7328
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Tested-by: Miklos Vajna <vmiklos@collabora.co.uk>