arm64: dts: hi3798cv200-poplar: add optee node

Add optee node, so OP-TEE driver is probed properly.
Acked-by: NJerome Forissier <jerome@forissier.org>
Signed-off-by: NIgor Opaniuk <igor.opaniuk@gmail.com>

arch/arm64/boot/dts/hisilicon/hi3798cv200-poplar.dts

@@ -71,6 +71,13 @@ reg_pcie: regulator-pcie {
 		gpio = <&gpio6 7 0>;
 		enable-active-high;
 	};
+
+	firmware {
+		optee {
+			compatible = "linaro,optee-tz";
+			method = "smc";
+		};
+	};
 };
 
 &ehci {