patch 8.2.0853: ml_delete() often called with FALSE argument

Problem:    ml_delete() often called with FALSE argument.
Solution:   Use ml_delete_flags(x, ML_DEL_MESSAGE) when argument is TRUE.
diff --git a/src/quickfix.c b/src/quickfix.c
index 4b3f164..f3ad4cd 100644
--- a/src/quickfix.c
+++ b/src/quickfix.c
@@ -4499,7 +4499,7 @@
 
 	// delete all existing lines
 	while ((curbuf->b_ml.ml_flags & ML_EMPTY) == 0)
-	    (void)ml_delete((linenr_T)1, FALSE);
+	    (void)ml_delete((linenr_T)1);
     }
 
     // Check if there is anything to display
@@ -4533,7 +4533,7 @@
 
 	if (old_last == NULL)
 	    // Delete the empty line which is now at the end
-	    (void)ml_delete(lnum + 1, FALSE);
+	    (void)ml_delete(lnum + 1);
     }
 
     // correct cursor position