patch 9.1.0100: Redrawing can be improved with undo and 'spell'

Problem:  When undoing with 'spell', redrawWinline() is called after
          changed_lines(), while later win_update() sets redraw type to
          UPD_NOT_VALID, even though w_redraw_top and w_redraw_bot are
          still valid.
Solution: Only set redraw type to UPD_NOT_VALID when inserting/deleting
          lines after parts of window has pending redraw, i.e., when
          changed_lines() is called after redrawWinline().
          (zeertzjq)

closes: #14019

Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/version.c b/src/version.c
index 7a9172a..602a2f9 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    100,
+/**/
     99,
 /**/
     98,