ARM: tegra: dts: add sflash controller dt entry

Nvidia's Tegra20 have the SPI (SFLASH) controller to
interface with spi flash device which is used for system
boot. Add DT entry for this controller.
Signed-off-by: NLaxman Dewangan <ldewangan@nvidia.com>
[swarren: move sflash node to keep file sorted]
Signed-off-by: NStephen Warren <swarren@nvidia.com>

arch/arm/boot/dts/tegra20.dtsi

@@ -147,6 +147,16 @@
 		status = "disabled";
 	};
 
+	spi@7000c380 {
+		compatible = "nvidia,tegra20-sflash";
+		reg = <0x7000c380 0x80>;
+		interrupts = <0 39 0x04>;
+		nvidia,dma-request-selector = <&apbdma 11>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+		status = "disabled";
+	};
+
 	i2c@7000c400 {
 		compatible = "nvidia,tegra20-i2c";
 		reg = <0x7000c400 0x100>;