MAINTAINERS: eth: mark Cavium liquidio as an Orphan

We haven't seen much review activity from the liquidio
maintainers for years. Reflect that reality in MAINTAINERS.
Our scripts report:

Subsystem CAVIUM LIQUIDIO NETWORK DRIVER
  Changes 30 / 87 (34%)
  Last activity: 2019-01-28
  Derek Chickles <dchickles@marvell.com>:
    Tags ac93e2fa 2019-01-28 00:00:00 1
  Satanand Burla <sburla@marvell.com>:
  Felix Manlunas <fmanlunas@marvell.com>:
    Tags ac93e2fa 2019-01-28 00:00:00 1
  Top reviewers:
    [5]: simon.horman@corigine.com
    [4]: keescook@chromium.org
    [4]: jiri@nvidia.com
  INACTIVE MAINTAINER Satanand Burla <sburla@marvell.com>
Acked-by: Derek Chickles <dchickles@marvell.com>
Link: https://lore.kernel.org/r/20240109164517.3063131-5-kuba@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

MAINTAINERS

@@ -4697,11 +4697,8 @@ F:	drivers/i2c/busses/i2c-octeon*
 F:	drivers/i2c/busses/i2c-thunderx*
 
 CAVIUM LIQUIDIO NETWORK DRIVER
-M:	Derek Chickles <dchickles@marvell.com>
-M:	Satanand Burla <sburla@marvell.com>
-M:	Felix Manlunas <fmanlunas@marvell.com>
 L:	netdev@vger.kernel.org
-S:	Supported
+S:	Orphan
 W:	http://www.marvell.com
 F:	drivers/net/ethernet/cavium/liquidio/