ARM: embestmx6boards: convert mars/riot boards to DM_ETH

Convert the boards to use DM_ETH.

Signed-off-by: Peter Robinson <pbrobinson@gmail.com>
Cc: "Eric BĂ©nard" <eric@eukrea.com>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Stefano Babic <sbabic@denx.de>
diff --git a/configs/riotboard_defconfig b/configs/riotboard_defconfig
index 1e5dc39..12af407 100644
--- a/configs/riotboard_defconfig
+++ b/configs/riotboard_defconfig
@@ -52,6 +52,8 @@
 CONFIG_SPI_FLASH_SST=y
 CONFIG_PHYLIB=y
 CONFIG_PHY_ATHEROS=y
+CONFIG_DM_ETH=y
+CONFIG_FEC_MXC=y
 CONFIG_MII=y
 CONFIG_MXC_UART=y
 CONFIG_SPI=y