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/ls1021aqds_nand_defconfig b/configs/ls1021aqds_nand_defconfig
index 7280d2d..3fb2a73 100644
--- a/configs/ls1021aqds_nand_defconfig
+++ b/configs/ls1021aqds_nand_defconfig
@@ -49,10 +49,10 @@
 CONFIG_FSL_CAAM=y
 CONFIG_SYS_FSL_DDR3=y
 CONFIG_MTD_NOR_FLASH=y
-CONFIG_PHYLIB=y
 CONFIG_NETDEVICES=y
 CONFIG_PHY_GIGE=y
 CONFIG_E1000=y
+CONFIG_TSEC_ENET=y
 CONFIG_PCI=y
 CONFIG_DM_PCI=y
 CONFIG_DM_PCI_COMPAT=y