ARM: zynq: Enable u-boot,dm-pre-reloc for sdhci

Enable u-boot,dm-pre-reloc for sdhci for zc706, zed and zybo.
And create aliases for it.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/dts/zynq-zc706.dts b/arch/arm/dts/zynq-zc706.dts
index 5088cfe..1ba3a1c 100644
--- a/arch/arm/dts/zynq-zc706.dts
+++ b/arch/arm/dts/zynq-zc706.dts
@@ -18,6 +18,7 @@
 		i2c0 = &i2c0;
 		serial0 = &uart1;
 		spi0 = &qspi;
+		mmc0 = &sdhci0;
 	};
 
 	memory {
@@ -291,6 +292,7 @@
 };
 
 &sdhci0 {
+	u-boot,dm-pre-reloc;
 	status = "okay";
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_sdhci0_default>;