net/sfc: reduce log level of tunnel restore info error

net/sfc: reduce log level of tunnel restore info error

OvS might invoke this API on its data path, out of sync
with its control plane. If the control path has already
deactivated the tunnel context entry, these invocations
will produce quite a few error printouts. Suppress that.

Fixes: 7e5b479803c3 ("net/sfc: implement control path operations in tunnel offload")
Cc: stable@dpdk.org
Signed-off-by: Ivan Malov <ivan.malov@oktetlabs.ru>
Reviewed-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>