mailmap: use private address for Michel Lespinasse

Link: https://lkml.kernel.org/r/20210602221225.49446-1-michel@lespinasse.org


Signed-off-by: Michel Lespinasse <michel@lespinasse.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>