mailmap: Update mail address for Boris Brezillon

Boris' email address has changed. Copy two entries from the Linux .mailmap
file.

Boris confirmed the new email address:
https://lists.denx.de/pipermail/u-boot/2019-December/393774.html



Cc: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>