arm/dt: Tegra: Add support-8bit to SDHCI nodes

For Seaboard's internal eMMC, this makes the difference between a
5.5MB/s and 10.2MB/s transfer rate. On Harmony, there wasn't any
measurable difference on my cheap/slow ~2MB/s card.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

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

@@ -66,5 +66,6 @@ sdhci@c8000600 {
 		cd-gpios = <&gpio 58 0>; /* gpio PH2 */
 		wp-gpios = <&gpio 59 0>; /* gpio PH3 */
 		power-gpios = <&gpio 70 0>; /* gpio PI6 */
+		support-8bit;
 	};
 };

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

@@ -25,4 +25,8 @@ sdhci@c8000400 {
 		wp-gpios = <&gpio 57 0>; /* gpio PH1 */
 		power-gpios = <&gpio 70 0>; /* gpio PI6 */
 	};
+
+	sdhci@c8000600 {
+		support-8bit;
+	};
 };