ARM: dts: gemini: add device_type on pci

Fixes DT warning on pci node by adding the missing device_type.
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

arch/arm/boot/dts/gemini.dtsi

@@ -286,6 +286,7 @@ pci@50000000 {
 			clock-names = "PCLK", "PCICLK";
 			pinctrl-names = "default";
 			pinctrl-0 = <&pci_default_pins>;
+			device_type = "pci";
 			#address-cells = <3>;
 			#size-cells = <2>;
 			#interrupt-cells = <1>;