MAINTAINERS: .mailmap: update Mattijs Korpershoek's email address

Update Mattijs Korpershoek's email address to @kernel.org.

Signed-off-by: Mattijs Korpershoek <mkorpershoek@kernel.org>
Link: https://lore.kernel.org/r/20250428-keypad-maintainers-v1-1-4e9c4afba415@kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Author: makohoek

.mailmap

@@ -472,6 +472,7 @@ Matthias Fuchs <socketcan@esd.eu> <matthias.fuchs@esd.eu>
 Matthieu Baerts <matttbe@kernel.org> <matthieu.baerts@tessares.net>
 Matthieu CASTET <castet.matthieu@free.fr>
 Matti Vaittinen <mazziesaccount@gmail.com> <matti.vaittinen@fi.rohmeurope.com>
+Mattijs Korpershoek <mkorpershoek@kernel.org> <mkorpershoek@baylibre.com>
 Matt Ranostay <matt@ranostay.sg> <matt.ranostay@konsulko.com>
 Matt Ranostay <matt@ranostay.sg> <matt@ranostay.consulting>
 Matt Ranostay <matt@ranostay.sg> Matthew Ranostay <mranostay@embeddedalley.com>

MAINTAINERS

@@ -14744,7 +14744,7 @@ F:	Documentation/devicetree/bindings/media/mediatek-jpeg-*.yaml
 F:	drivers/media/platform/mediatek/jpeg/
 
 MEDIATEK KEYPAD DRIVER
-M:	Mattijs Korpershoek <mkorpershoek@baylibre.com>
+M:	Mattijs Korpershoek <mkorpershoek@kernel.org>
 S:	Supported
 F:	Documentation/devicetree/bindings/input/mediatek,mt6779-keypad.yaml
 F:	drivers/input/keyboard/mt6779-keypad.c