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: NHeinrich Schuchardt <xypron.glpk@gmx.de>

.mailmap

@@ -20,6 +20,8 @@ Allen Martin <amartin@nvidia.com>
 Andreas Bießmann <andreas.devel@googlemail.com>
 Andreas Bießmann <andreas@biessmann.org>
 Aneesh V <aneesh@ti.com>
+Boris Brezillon <bbrezillon@kernel.org> <boris.brezillon@bootlin.com>
+Boris Brezillon <bbrezillon@kernel.org> <boris.brezillon@free-electrons.com>
 Dirk Behme <dirk.behme@googlemail.com>
 Fabio Estevam <fabio.estevam@nxp.com>
 Jagan Teki <402jagan@gmail.com>