treewide: Migrate CONFIG_TSEC_ENET to Kconfig

Migrate the CONFIG_TSEC_ENET option to Kconfig.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
diff --git a/configs/strider_con_defconfig b/configs/strider_con_defconfig
index b860250..abe6458 100644
--- a/configs/strider_con_defconfig
+++ b/configs/strider_con_defconfig
@@ -31,7 +31,8 @@
 CONFIG_CMD_EXT2=y
 CONFIG_DOS_PARTITION=y
 CONFIG_MTD_NOR_FLASH=y
-CONFIG_PHYLIB=y
+CONFIG_NETDEVICES=y
+CONFIG_TSEC_ENET=y
 CONFIG_CONS_INDEX=2
 CONFIG_SYS_NS16550=y
 CONFIG_OF_LIBFDT=y