Replace include guards with pragma once in several header files in compilerplugins Change-Id: I9cc586977dc7ade9278d93396c3efcd13acba286 Reviewed-on: https://gerrit.libreoffice.org/c/core/+/121089 Tested-by: Ilmari Lauhakangas <ilmari.lauhakangas@libreoffice.org> Reviewed-by: Ilmari Lauhakangas <ilmari.lauhakangas@libreoffice.org>