net/failsafe: advertise supported RSS functions

net/failsafe: advertise supported RSS functions

Advertise failsafe supported RSS functions as part of dev_infos_get
callback. Set failsafe default RSS hash functions to be:
ETH_RSS_IP, ETH_RSS_UDP, and ETH_RSS_TCP.
The result of failsafe RSS hash functions is the logical AND of the
RSS hash functions among all failsafe sub_devices and failsafe own
defaults.

Previous to this commit RSS support was reported as none. Since the
introduction of [1] it is required that all RSS configurations be
verified.

[1] commit 8863a1fbfc66 ("ethdev: add supported hash function check")

Signed-off-by: Ophir Munk <ophirmu@mellanox.com>
Acked-by: Gaetan Rivet <gaetan.rivet@6wind.com>