bond: Disable TLS features indication

bond: Disable TLS features indication

Bond agnostically interacts with TLS device-offload requests via the
.ndo_sk_get_lower_dev operation. Return value is true iff bond
guarantees fixed mapping between the TLS connection and a lower netdev.

Due to this nature, the bond TLS device offload features are not
explicitly controllable in the bond layer. As of today, these are
read-only values based on the evaluation of bond_sk_check().  However,
this indication might be incorrect and misleading, when the feature bits
are "fixed" by some dependency features.  For example,
NETIF_F_HW_TLS_TX/RX are forcefully cleared in case the corresponding
checksum offload is disabled. But in fact the bond ability to still
offload TLS connections to the lower device is not hurt.

This means that these bits can not be trusted, and hence better become
unused.

This patch revives some old discussion [1] and proposes a much simpler
solution: Clear the bond's TLS features bits. Everyone should stop
reading them.

[1] https://lore.kernel.org/netdev/20210526095747.22446-1-tariqt@nvidia.com/

Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Gal Pressman <gal@nvidia.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20221025105300.4718-1-tariqt@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>