boards: b_l072z_lrwan1: enable power management support

Enable lptim1 and configure the suspend power state for b_l072z_lrwan1.

Signed-off-by: Fabio Baltieri <[email protected]>

Author: fabiobaltieri

boards/arm/b_l072z_lrwan1/b_l072z_lrwan1.dts

@@ -57,6 +57,22 @@
 		eeprom-0 = &eeprom;
 		lora0 = &lora;
 	};
+
+	power-states {
+		stop: stop {
+			compatible = "zephyr,power-state";
+			power-state-name = "suspend-to-idle";
+			min-residency-us = <100>;
+		};
+	};
+};
+
+&cpu0 {
+	cpu-power-states = <&stop>;
+};
+
+&lptim1 {
+	status = "okay";
 };
 
 &clk_hsi {

dts/arm/st/l0/stm32l0.dtsi

@@ -21,7 +21,7 @@
 		#address-cells = <1>;
 		#size-cells = <0>;
 
-		cpu@0 {
+		cpu0: cpu@0 {
 			device_type = "cpu";
 			compatible = "arm,cortex-m0+";
 			reg = <0>;