Replace sleep with px4_sleep

This is another step to isolate time from the system.

src/modules/commander/accelerometer_calibration.cpp

@@ -840,7 +840,7 @@ int do_level_calibration(orb_advert_t *mavlink_log_pub)
 	while (hrt_elapsed_time(&start) < settle_time * 1000000) {
 		calibration_log_info(mavlink_log_pub, CAL_QGC_PROGRESS_MSG,
 				     (int)(90 * hrt_elapsed_time(&start) / 1e6f / (float)settle_time));
-		sleep(settle_time / 10);
+		px4_sleep(settle_time / 10);
 	}
 
 	start = hrt_absolute_time();

src/modules/commander/airspeed_calibration.cpp

@@ -60,7 +60,7 @@ static const char *sensor_name = "airspeed";
 
 static void feedback_calibration_failed(orb_advert_t *mavlink_log_pub)
 {
-	sleep(5);
+	px4_sleep(5);
 	calibration_log_critical(mavlink_log_pub, CAL_QGC_FAILED_MSG, sensor_name);
 }
 
@@ -284,7 +284,7 @@ normal_return:
 	px4_close(diff_pres_sub);
 
 	// This give a chance for the log messages to go out of the queue before someone else stomps on then
-	sleep(1);
+	px4_sleep(1);
 
 	return result;
 

src/modules/commander/rc_check.cpp

@@ -223,7 +223,7 @@ int rc_calibration_check(orb_advert_t *mavlink_log_pub, bool report_fail, bool i
 	}
 
 	if (channels_failed) {
-		sleep(2);
+		px4_sleep(2);
 
 		if (report_fail) {
 			mavlink_log_critical(mavlink_log_pub, "%d config error%s for %d RC channel%s.",