arm64: dts: rockchip: Add mmc aliases for rk3562-linux.dtsi

This series in order to have the default MMC alias.

The mmc default alias:
            mmc0 = &sdhci;
            mmc1 = &sdmmc0;
            mmc2 = &sdmmc1;

The Linux OS have the post-build.sh to handle the rootfs,
and export RK_EXTRA_PARTITIONS for setting the PARTITIONS.

Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Change-Id: I28ae38a7aaf35c6f584879c19a339ff6079d059d

arch/arm64/boot/dts/rockchip/rk3562-linux.dtsi

@@ -5,6 +5,12 @@
  */
 
 / {
+	aliases {
+		mmc0 = &sdhci;
+		mmc1 = &sdmmc0;
+		mmc2 = &sdmmc1;
+	};
+
 	chosen: chosen {
 		bootargs = "earlycon=uart8250,mmio32,0xff210000 console=ttyFIQ0 root=PARTUUID=614e0000-0000 rw rootwait";
 	};