Added TI ina226 I2C power monitor (#11755)

msg/CMakeLists.txt

@@ -88,6 +88,7 @@ set(msg_files
 	position_setpoint.msg
 	position_setpoint_triplet.msg
 	power_button_state.msg
+	power_monitor.msg
 	pwm_input.msg
 	qshell_req.msg
 	qshell_retval.msg

msg/power_monitor.msg

@@ -0,0 +1,15 @@
+# power monitor message
+
+uint64 timestamp			# Time since system start (microseconds)
+
+float32 voltage_v			# Voltage in volts, 0 if unknown
+float32 current_a		    # Current in amperes, -1 if unknown
+float32 power_w		        # power in watts, -1 if unknown
+int16 rconf
+int16 rsv
+int16 rbv
+int16 rp
+int16 rc
+int16 rcal
+int16 me
+int16 al