arm64: dts: zynqmp: Use mmc@ instead sdhci@

mmc name is recommended based on devicetree specification.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

arch/arm64/boot/dts/xilinx/zynqmp.dtsi

@@ -484,7 +484,7 @@ sata: ahci@fd0c0000 {
 			interrupts = <0 133 4>;
 		};
 
-		sdhci0: sdhci@ff160000 {
+		sdhci0: mmc@ff160000 {
 			compatible = "arasan,sdhci-8.9a";
 			status = "disabled";
 			interrupt-parent = <&gic>;
@@ -493,7 +493,7 @@ sdhci0: sdhci@ff160000 {
 			clock-names = "clk_xin", "clk_ahb";
 		};
 
-		sdhci1: sdhci@ff170000 {
+		sdhci1: mmc@ff170000 {
 			compatible = "arasan,sdhci-8.9a";
 			status = "disabled";
 			interrupt-parent = <&gic>;