filechk displays two short logs; CHK for creating a temporary file,
and UPD for really updating the target.

IMHO, the build system can be quiet when the target file has not
been updated.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: NSam Ravnborg <sam@ravnborg.org>