ARM: dts: imx7d-colibri-emmc: Add usdhc aliases

Add mmc aliases to ensure a consistent mmc device naming across the
Toradex SoM family, with this commit mmc0 is the on-module eMMC
boot device and the not available mmc interfaces are removed.
Signed-off-by: Hiago De Franco <hiago.franco@toradex.com>
Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/nxp/imx/imx7d-colibri-emmc.dtsi

@@ -11,6 +11,10 @@ aliases {
 		/* Required to properly pass MAC addresses from bootloader. */
 		ethernet0 = &fec1;
 		ethernet1 = &fec2;
+		mmc0 = &usdhc3; /* eMMC */
+		mmc1 = &usdhc1; /* MMC/SD slot */
+		/delete-property/ mmc2;
+		/delete-property/ mmc3;
 	};
 
 	memory@80000000 {