net/failsafe: fix Rx safe check compiler hint

net/failsafe: fix Rx safe check compiler hint

failsafe_rx_burst function is used when there are no sub-devices or at
least one of them has been removed, on the other hand, when all the
sub-devices are present, failsafe_rx_burst_fast function is used.

So it's really expected that some of the sub-devices will be unsafe for
Rx burst in failsafe_rx_burst execution.

Remove unlikely compiler hint from fs_rx_unsafe calling.

Fixes: a46f8d584eb8 ("net/failsafe: add fail-safe PMD")
Cc: stable@dpdk.org
Signed-off-by: Matan Azrad <matan@mellanox.com>
Acked-by: Gaetan Rivet <gaetan.rivet@6wind.com>