Convert CONFIG_FSL_USDHC to Kconfig

This converts the following to Kconfig:
   CONFIG_FSL_USDHC

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/imx8mm-cl-iot-gate-optee_defconfig b/configs/imx8mm-cl-iot-gate-optee_defconfig
index 79d4821..29d0601 100644
--- a/configs/imx8mm-cl-iot-gate-optee_defconfig
+++ b/configs/imx8mm-cl-iot-gate-optee_defconfig
@@ -81,7 +81,7 @@
 CONFIG_DM_KEYBOARD=y
 CONFIG_SUPPORT_EMMC_RPMB=y
 CONFIG_SUPPORT_EMMC_BOOT=y
-CONFIG_FSL_ESDHC_IMX=y
+CONFIG_FSL_USDHC=y
 CONFIG_DM_SPI_FLASH=y
 CONFIG_PHYLIB=y
 CONFIG_PHY_ATHEROS=y