media: MAINTAINERS: Update MAINTAINERS for Renesas DRIF driver

Add Fabrizio castro and remove Ramesh Shanmugasundaram.

Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Reviewed-by: Ramesh Shanmugasundaram <rashanmu@gmail.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>