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>
diff --git a/include/configs/sbc8349.h b/include/configs/sbc8349.h
index aa515ea..37a8f87 100644
--- a/include/configs/sbc8349.h
+++ b/include/configs/sbc8349.h
@@ -662,6 +662,7 @@
 #define CONFIG_ENV_OVERWRITE
 
 #if defined(CONFIG_TSEC_ENET)
+#define CONFIG_HAS_ETH0
 #define CONFIG_ETHADDR		00:a0:1e:a0:13:8d
 #define CONFIG_HAS_ETH1
 #define CONFIG_ETH1ADDR		00:a0:1e:a0:13:8e