Move PHY_MICREL and PHY_MICREL_KSZ90X1 to Kconfig

Signed-off-by: Alexandru Gagniuc <alex.g@adaptrum.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/configs/stv0991_defconfig b/configs/stv0991_defconfig
index 6940696..f03e659 100644
--- a/configs/stv0991_defconfig
+++ b/configs/stv0991_defconfig
@@ -23,6 +23,7 @@
 # CONFIG_MMC is not set
 CONFIG_SPI_FLASH_STMICRO=y
 CONFIG_SPI_FLASH_WINBOND=y
+CONFIG_PHY_MICREL=y
 CONFIG_NETDEVICES=y
 CONFIG_ETH_DESIGNWARE=y
 CONFIG_CADENCE_QSPI=y