selftests: mlxsw: Add mlxsw lib

Add mlxsw lib for common defines, helpers etc.
Signed-off-by: Shalom Toledo <shalomt@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/drivers/net/mlxsw/mlxsw_lib.sh

+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+##############################################################################
+# Defines
+
+if [[ ! -v MLXSW_CHIP ]]; then
+	MLXSW_CHIP=$(devlink -j dev info $DEVLINK_DEV | jq -r '.[][]["driver"]')
+	if [ -z "$MLXSW_CHIP" ]; then
+		echo "SKIP: Device $DEVLINK_DEV doesn't support devlink info command"
+		exit 1
+	fi
+fi