refactor: print info on overshoot after processing all data

It may happen (race-condition) that "Correcting overshoot" info
message appears in the middle of the records output. This is
missleading. Change the approach and only print info on overshoot
correction after all the data were processed. This way they will never
mix with the records output.

src/sardana/macroserver/scan/gscan.py

@@ -2674,7 +2674,6 @@ def on_waypoints_end(self, restore_positions=None):
         if restore_positions is not None:
             self._restore_motors()  # first restore motors backup
             self._setFastMotions()  # then try to go even faster (limits)
-            self.macro.info("Correcting overshoot...")
             self._physical_motion.move(restore_positions)
         self.motion_end_event.set()
         self.cleanup()
@@ -2683,6 +2682,10 @@ def on_waypoints_end(self, restore_positions=None):
         self.join_thread_pool()
         self.debug("All data events are processed")
         self.data.endRecords()
+        if restore_positions is not None:
+            self.macro.info("Overshoot was corrected")
+        else:
+            self.macro.info("Overshoot was not corrected")
 
         # Note: The commented out code below works, but due to an issue with
         # output of the last measurement point, it should not be enabled yet.