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/pico-imx7d_defconfig b/configs/pico-imx7d_defconfig
index f011b5c..02d990b 100644
--- a/configs/pico-imx7d_defconfig
+++ b/configs/pico-imx7d_defconfig
@@ -22,6 +22,7 @@
 CONFIG_CMD_EXT4=y
 CONFIG_CMD_EXT4_WRITE=y
 CONFIG_CMD_FAT=y
+CONFIG_PHYLIB=y
 CONFIG_USB=y
 CONFIG_USB_EHCI_HCD=y
 CONFIG_MXC_USB_OTG_HACTIVE=y