dt-bindings: mediatek,mt6779-keypad: Update Mattijs' email address

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

Signed-off-by: Mattijs Korpershoek <mkorpershoek@kernel.org>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://lore.kernel.org/r/20250428-keypad-email-v1-1-dde6ac76725b@kernel.org


Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>