fix runtime threshold using us instead of ms

Author: sctanf

src/system/power.c

@@ -526,7 +526,7 @@ static void power_thread(void)
 		// use estimated remaining runtime or pptt for battery_low
 		uint64_t runtime = sys_get_battery_remaining_time_estimate();
 		bool runtime_valid = runtime;
-		bool runtime_low = k_ticks_to_us_floor64(runtime) < CONFIG_3_SETTINGS_READ(CONFIG_3_BATTERY_LOW_RUNTIME_THRESHOLD);
+		bool runtime_low = k_ticks_to_ms_floor64(runtime) < CONFIG_3_SETTINGS_READ(CONFIG_3_BATTERY_LOW_RUNTIME_THRESHOLD);
 		bool pptt_low = current_battery_pptt < 1000;
 		if (battery_available && !battery_low && (runtime_valid ? runtime_low : pptt_low))
 			battery_low = true;