MAINTAINERS: add netup_unidvb maintainer

Adding/restoring maintainership for the following drivers:
F:     drivers/media/pci/netup_unidvb/*
F:     drivers/media/dvb-frontends/helene*
F:     drivers/media/dvb-frontends/horus3a*
F:     drivers/media/dvb-frontends/lnbh25*
F:     drivers/media/dvb-frontends/ascot2e*
F:     drivers/media/dvb-frontends/cxd2841er*

Signed-off-by: Abylay Ospan <aospan@amazon.com>
Link: https://lore.kernel.org/r/20241023163425.30492-1-aospan@amazon.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>