MAINTAINERS: update Claudiu Beznea's email address

Update MAINTAINERS entries with a valid email address as the Microchip
one is no longer valid.

Acked-by: Conor Dooley <conor.dooley@microchip.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>
Acked-by: Sebastian Reichel <sre@kernel.org>
Link: https://lore.kernel.org/r/20230804050007.235799-1-claudiu.beznea@tuxon.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>