Add CONFIG_HAS_ETH0 to all boards with TSEC

The 85xx code now relies on CONFIG_HAS_ETH0 to determine whether
to update TSEC1's device-tree node, so we need to add it
to all the boards with TSECs.  Do this for 83xx and 86xx, too,
since they will eventually do something similar.

Signed-off-by: Andy Fleming <afleming@freescale.com>

include/configs/sbc8641d.h

diff --git a/include/configs/sbc8641d.h b/include/configs/sbc8641d.h
index 760b754..3525ab4 100644
--- a/include/configs/sbc8641d.h
+++ b/include/configs/sbc8641d.h
@@ -546,6 +546,7 @@
 #define CONFIG_ETH3ADDR  02:E0:0C:00:03:FD
 #endif
 
+#define CONFIG_HAS_ETH0		1
 #define CONFIG_HAS_ETH1		1
 #define CONFIG_HAS_ETH2		1
 #define CONFIG_HAS_ETH3		1