ARM: at91/defconfig: at91_dt: remove ARM_AT91_ETHER

CONFIG_ARM_AT91_ETHER doesn't exist anymore, both drivers have been merged
in the macb driver.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Olof Johansson <olof@lixom.net>

arch/arm/configs/at91_dt_defconfig

@@ -73,7 +73,6 @@ CONFIG_SCSI=y
 CONFIG_BLK_DEV_SD=y
 # CONFIG_SCSI_LOWLEVEL is not set
 CONFIG_NETDEVICES=y
-CONFIG_ARM_AT91_ETHER=y
 CONFIG_MACB=y
 # CONFIG_NET_VENDOR_BROADCOM is not set
 CONFIG_DM9000=y