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/MPC8315ERDB_defconfig b/configs/MPC8315ERDB_defconfig
index 74d886c..b40b2c1 100644
--- a/configs/MPC8315ERDB_defconfig
+++ b/configs/MPC8315ERDB_defconfig
@@ -18,6 +18,7 @@
 CONFIG_CMD_MTDPARTS=y
 # CONFIG_MMC is not set
 CONFIG_MTD_NOR_FLASH=y
+CONFIG_PHYLIB=y
 CONFIG_SYS_NS16550=y
 CONFIG_USB=y
 CONFIG_USB_EHCI_HCD=y