dpaa2-eth: Fix compile error due to missing devlink support

dpaa2-eth: Fix compile error due to missing devlink support

The dpaa2 driver depends on devlink, so it should select
NET_DEVLINK in order to fix compile errors, such as:

drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.o: in function `dpaa2_eth_rx_err':
dpaa2-eth.c:(.text+0x3cec): undefined reference to `devlink_trap_report'
drivers/net/ethernet/freescale/dpaa2/dpaa2-eth-devlink.o: in function `dpaa2_eth_dl_info_get':
dpaa2-eth-devlink.c:(.text+0x160): undefined reference to `devlink_info_driver_name_put'

Fixes: ceeb03ad8e22 ("dpaa2-eth: add basic devlink support")
Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Link: https://lore.kernel.org/r/20201123163553.1666476-1-ciorneiioana@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>