treewide: Migrate CONFIG_FSL_ESDHC to Kconfig

Migrate the CONFIG_FSL_ESDHC option to Kconfig.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
diff --git a/configs/mx6sxsabresd_defconfig b/configs/mx6sxsabresd_defconfig
index 2856a7f..c467588 100644
--- a/configs/mx6sxsabresd_defconfig
+++ b/configs/mx6sxsabresd_defconfig
@@ -34,6 +34,7 @@
 CONFIG_DM_GPIO=y
 CONFIG_DM_I2C=y
 CONFIG_DM_MMC=y
+CONFIG_FSL_ESDHC=y
 CONFIG_SPI_FLASH=y
 CONFIG_SPI_FLASH_BAR=y
 CONFIG_PHYLIB=y