ARM: dts: qcom: ipq4019: add more labels

Lets add labels to more commonly used nodes for easier modification in board DTS files.
Signed-off-by: Robert Marko <robert.marko@sartura.hr>
Cc: Luka Perkov <luka.perkov@sartura.hr>
Link: https://lore.kernel.org/r/20200909195640.3127341-2-robert.marko@sartura.hrSigned-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

arch/arm/boot/dts/qcom-ipq4019.dtsi

@@ -190,7 +190,7 @@ gcc: clock-controller@1800000 {
 			reg = <0x1800000 0x60000>;
 		};
 
-		rng@22000 {
+		prng: rng@22000 {
 			compatible = "qcom,prng";
 			reg = <0x22000 0x140>;
 			clocks = <&gcc GCC_PRNG_AHB_CLK>;
@@ -300,7 +300,7 @@ cryptobam: dma@8e04000 {
 			status = "disabled";
 		};
 
-		crypto@8e3a000 {
+		crypto: crypto@8e3a000 {
 			compatible = "qcom,crypto-v5.1";
 			reg = <0x08e3a000 0x6000>;
 			clocks = <&gcc GCC_CRYPTO_AHB_CLK>,
@@ -386,7 +386,7 @@ blsp1_uart2: serial@78b0000 {
 			dma-names = "rx", "tx";
 		};
 
-		watchdog@b017000 {
+		watchdog: watchdog@b017000 {
 			compatible = "qcom,kpss-wdt", "qcom,kpss-wdt-ipq4019";
 			reg = <0xb017000 0x40>;
 			clocks = <&sleep_clk>;