mmc: Kconfig: Add Arasan SDHCI entry

Add Arasan SDHCI entry to Kconfig and fix all references.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/configs/zynq_picozed_defconfig b/configs/zynq_picozed_defconfig
index fbc603f..f34e2e3 100644
--- a/configs/zynq_picozed_defconfig
+++ b/configs/zynq_picozed_defconfig
@@ -10,4 +10,5 @@
 # CONFIG_CMD_SETEXPR is not set
 CONFIG_NET_RANDOM_ETHADDR=y
 CONFIG_SPL_DM_SEQ_ALIAS=y
+CONFIG_ZYNQ_SDHCI=y
 CONFIG_ZYNQ_GEM=y