devlink: don't take instance lock around eswitch mode set

Changing switch mode may want to register and unregister devlink
ports.  Therefore similarly to DEVLINK_CMD_PORT_SPLIT/UNSPLIT it
should not take the instance lock.  Drivers don't depend on existing
locking since it's a very recent addition.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/devlink.c

@@ -2756,7 +2756,8 @@ static const struct genl_ops devlink_nl_ops[] = {
 		.doit = devlink_nl_cmd_eswitch_set_doit,
 		.policy = devlink_nl_policy,
 		.flags = GENL_ADMIN_PERM,
-		.internal_flags = DEVLINK_NL_FLAG_NEED_DEVLINK,
+		.internal_flags = DEVLINK_NL_FLAG_NEED_DEVLINK |
+				  DEVLINK_NL_FLAG_NO_LOCK,
 	},
 	{
 		.cmd = DEVLINK_CMD_DPIPE_TABLE_GET,