memory: tegra: populate dt subnodes

Tegra210b01 uses tegra186-emc driver as emc clock is controlled by BPMP.
However, this driver expects emc as subnode of mc. Adjust Tegra30 mc
probe routine to populate subnodes.

drivers/memory/tegra/mc.c

@@ -541,6 +541,10 @@ int tegra30_mc_probe(struct tegra_mc *mc)
 	if (err < 0)
 		return dev_err_probe(mc->dev, err, "failed to setup timings\n");
 
+	err = of_platform_populate(mc->dev->of_node, NULL, NULL, mc->dev);
+	if (err < 0)
+		return err;
+
 	return 0;
 }