ARM: dt: tegra cardhu: fix typo in SDHCI node name

Cardhu's eMMC controller is on sdhci@78000600, not sdhci@78000400.
Fix the typo. This roughly doubles the IO performance, since the
support-8bit property actually takes effect.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Cc: stable@kernel.org # v3.4

arch/arm/boot/dts/tegra-cardhu.dts

@@ -152,7 +152,7 @@ sdhci@78000400 {
 		status = "disable";
 	};
 
-	sdhci@78000400 {
+	sdhci@78000600 {
 		support-8bit;
 	};