net: dpaa2: fix dependency of config FSL_DPAA2_ETH

The NETDEVICES dependency and ETHERNET dependency hadn't
been required since dpaa2-eth was moved out of staging.
Also allowed COMPILE_TEST for dpaa2-eth.
Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/freescale/dpaa2/Kconfig

 config FSL_DPAA2_ETH
 	tristate "Freescale DPAA2 Ethernet"
 	depends on FSL_MC_BUS && FSL_MC_DPIO
-	depends on NETDEVICES && ETHERNET
+	depends on ARCH_LAYERSCAPE || COMPILE_TEST
 	help
 	  This is the DPAA2 Ethernet driver supporting Freescale SoCs
 	  with DPAA2 (DataPath Acceleration Architecture v2).