media: MAINTAINERS: add Dafna Hirschfeld for rkisp1

Add Dafna Hirschfeld to rkisp1 maintainers list

Signed-off-by: Helen Koike <helen.koike@collabora.com>
Acked-by: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>