MAINTAINERS: remove obsolete file entry in NETWORKING DRIVERS

MAINTAINERS: remove obsolete file entry in NETWORKING DRIVERS

Commit d8f87aa5fa0a ("net: remove HIPPI support and RoadRunner HIPPI
driver") removes the hippidevice header file, but misses that there is
still a file entry in MAINTAINERS referring to it.

Remove the obsolete file entry in NETWORKING DRIVERS.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@redhat.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260122074609.151058-1-lukas.bulwahn@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>