patch 8.2.4379: an empty change is reported to a listener

Problem:    An empty change is reported to a listener.
Solution:   Do not report an empty change. (closes #9768)  Remove unused
            return value.
diff --git a/src/change.c b/src/change.c
index 25a0841..771f767 100644
--- a/src/change.c
+++ b/src/change.c
@@ -155,9 +155,8 @@
 /*
  * Check if the change at "lnum" is above or overlaps with an existing
  * change. If above then flush changes and invoke listeners.
- * Returns TRUE if the change was merged.
  */
-    static int
+    static void
 check_recorded_changes(
 	buf_T		*buf,
 	linenr_T	lnum,
@@ -185,7 +184,6 @@
 	    }
 	}
     }
-    return FALSE;
 }
 
 /*
@@ -206,8 +204,7 @@
 
     // If the new change is going to change the line numbers in already listed
     // changes, then flush.
-    if (check_recorded_changes(curbuf, lnum, lnume, xtra))
-	return;
+    check_recorded_changes(curbuf, lnum, lnume, xtra);
 
     if (curbuf->b_recorded_changes == NULL)
     {