Convert CONFIG_PHYLIB et al to Kconfig

This converts the following to Kconfig:
   CONFIG_PHYLIB
   CONFIG_PHY_ATHEROS
   CONFIG_PHY_GIGE
   CONFIG_MII

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/imx8mq_phanbell_defconfig b/configs/imx8mq_phanbell_defconfig
index 3de517c..4b7fafe 100644
--- a/configs/imx8mq_phanbell_defconfig
+++ b/configs/imx8mq_phanbell_defconfig
@@ -58,8 +58,11 @@
 CONFIG_SPL_SYS_I2C_LEGACY=y
 CONFIG_SUPPORT_EMMC_BOOT=y
 CONFIG_FSL_USDHC=y
+CONFIG_PHYLIB=y
 CONFIG_DM_ETH=y
+CONFIG_PHY_GIGE=y
 CONFIG_FEC_MXC=y
+CONFIG_MII=y
 CONFIG_PINCTRL=y
 CONFIG_PINCTRL_IMX8M=y
 CONFIG_SPL_POWER_LEGACY=y