Add PPS capture message to logged topics, simplify timestamp logic and small cleanup

src/drivers/camera_capture/camera_capture.cpp

@@ -193,10 +193,8 @@ CameraCapture::publish_trigger()
 
 
 	if (_pps_hrt_timestamp > 0) {
-		// Current RTC time (RTC time captured by the PPS module + elapsed time since capture)
-		uint64_t gps_utc_time = _pps_rtc_timestamp + hrt_elapsed_time(&_pps_hrt_timestamp);
-		// Current RTC time - elapsed time since capture interrupt event
-		trigger.timestamp_utc = gps_utc_time - hrt_elapsed_time(&trigger.timestamp);
+		// Last PPS RTC time + elapsed time to the camera capture interrupt
+		trigger.timestamp_utc = _pps_rtc_timestamp + (trigger.timestamp - _pps_hrt_timestamp);
 
 	} else {
 		// No PPS capture received, use RTC clock as fallback

src/drivers/camera_capture/camera_capture.hpp

@@ -132,8 +132,8 @@ private:
 	hrt_abstime		_last_trig_time{0};
 	uint32_t 		_capture_overflows{0};
 
-	uint64_t    _pps_hrt_timestamp{0};
-	uint64_t    _pps_rtc_timestamp{0};
+	hrt_abstime	_pps_hrt_timestamp{0};
+	uint64_t		_pps_rtc_timestamp{0};
 
 	// Signal capture callback
 	void			capture_callback(uint32_t chan_index, hrt_abstime edge_time, uint32_t edge_state, uint32_t overflow);