patch 8.0.1797: terminal window is redrawn too often

Problem:    Terminal window is redrawn too often and scrolling is repeated.
Solution:   Don't scroll immediately but only when redrawing.  Avoid redrawing
            the whole terminal window on every change.

src/version.c

@@ -761,6 +761,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1797,
 /**/
     1796,
 /**/