Since the commit 84cba72956fd ("dpaa2-switch: integrate
the MAC endpoint support") included dpaa2-mac.o in the driver,
but it didn't select PCS_LYNX, PHYLINK and FSL_XGMAC_MDIO. it
will lead to link error, such as
undefined reference to `phylink_ethtool_ksettings_set'
undefined reference to `lynx_pcs_create_fwnode'

And the same reason as the commit d2624e70a2f53 ("dpaa2-eth: select
XGMAC_MDIO for MDIO bus support"), enable the FSL_XGMAC_MDIO Kconfig
option in order to have MDIO access to internal and external PHYs.

Fixes: 84cba72956fd ("dpaa2-switch: integrate the MAC endpoint support")
Suggested-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Cai Xinchen <caixinchen1@huawei.com>
---
 drivers/net/ethernet/freescale/dpaa2/Kconfig | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/freescale/dpaa2/Kconfig b/drivers/net/ethernet/freescale/dpaa2/Kconfig
index d029b69c3f18..44637ec7c25d 100644
--- a/drivers/net/ethernet/freescale/dpaa2/Kconfig
+++ b/drivers/net/ethernet/freescale/dpaa2/Kconfig
@@ -34,6 +34,9 @@ config FSL_DPAA2_SWITCH
 	tristate "Freescale DPAA2 Ethernet Switch"
 	depends on BRIDGE || BRIDGE=n
 	depends on NET_SWITCHDEV
+	select PHYLINK
+	select PCS_LYNX
+	select FSL_XGMAC_MDIO
 	help
 	  Driver for Freescale DPAA2 Ethernet Switch. This driver manages
 	  switch objects discovered on the Freeescale MC bus.
-- 
2.34.1