ARM: tegra: Add EMC to Tegra124 device tree

This adds a node for the EMC memory controller. It is always enabled, but only
provides read-only functionality without board-specific timing tables.

Signed-off-by: Mikko Perttunen <[e-mail]>
Signed-off-by: Tomeu Vizoso <[e-mail]>
Signed-off-by: Thierry Reding <[e-mail]>

arch/arm/boot/dts/tegra124.dtsi

···
 		reg = <0x0 0x60006000 0x0 0x1000>;
 		#clock-cells = <1>;
 		#reset-cells = <1>;
+		nvidia,external-memory-controller = <&emc>;
 	};
 
 	flow-controller@0,60007000 {
···
 		interrupts = <GIC_SPI 77 IRQ_TYPE_LEVEL_HIGH>;
 
 		#iommu-cells = <1>;
+	};
+
+	emc: emc@0,7001b000 {
+		compatible = "nvidia,tegra124-emc";
+		reg = <0x0 0x7001b000 0x0 0x1000>;
+
+		nvidia,memory-controller = <&mc>;
 	};
 
 	sata@0,70020000 {