Move PHYLIB to Kconfig

Signed-off-by: Alexandru Gagniuc <alex.g@adaptrum.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/configs/MPC8536DS_defconfig b/configs/MPC8536DS_defconfig
index 65a1f9e..7c5a420 100644
--- a/configs/MPC8536DS_defconfig
+++ b/configs/MPC8536DS_defconfig
@@ -24,6 +24,7 @@
 CONFIG_MTD_NOR_FLASH=y
 CONFIG_SPI_FLASH=y
 CONFIG_SPI_FLASH_SPANSION=y
+CONFIG_PHYLIB=y
 CONFIG_NETDEVICES=y
 CONFIG_E1000=y
 CONFIG_SYS_NS16550=y