Simply compare what's currently in the glossary with the actual code in base.bbclass: FILESPATH = "${@base_set_filespath(["${FILE_DIRNAME}/${BP}", "${FILE_DIRNAME}/${BPN}", "${FILE_DIRNAME}/files"], d)}"
Updated the glossary to match the setting in base.bbclass. See at http://www.yoctoproject.org/docs/1.4/ref-manual/ref-manual.html#var-FILESPATH.