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/mpc8308_p1m_defconfig b/configs/mpc8308_p1m_defconfig
index 54b126b..bdb5679 100644
--- a/configs/mpc8308_p1m_defconfig
+++ b/configs/mpc8308_p1m_defconfig
@@ -19,6 +19,7 @@
 CONFIG_BOOTP_HOSTNAME=y
 # CONFIG_MMC is not set
 CONFIG_MTD_NOR_FLASH=y
-CONFIG_PHYLIB=y
+CONFIG_NETDEVICES=y
+CONFIG_TSEC_ENET=y
 CONFIG_SYS_NS16550=y
 CONFIG_OF_LIBFDT=y