ravb: Remove setting of RX software timestamp

ravb: Remove setting of RX software timestamp

[ Upstream commit 277901ee3a2620679e2c8797377d2a72f4358068 ]

The responsibility for reporting of RX software timestamp has moved to
the core layer (see __ethtool_get_ts_info()), remove usage from the
device drivers.

Reviewed-by: Carolina Jubran <cjubran@nvidia.com>
Reviewed-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
Signed-off-by: Gal Pressman <gal@nvidia.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Link: https://patch.msgid.link/20240901112803.212753-8-gal@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 126e799602f4 ("net: ravb: Only advertise Rx/Tx timestamps if hardware supports it")
Signed-off-by: Sasha Levin <sashal@kernel.org>