patch 8.0.0938: scrolling in terminal window is inefficient

Problem:    Scrolling in terminal window is inefficient.
Solution:   Use win_del_lines().
diff --git a/src/version.c b/src/version.c
index 36075d9..a8b07dc 100644
--- a/src/version.c
+++ b/src/version.c
@@ -770,6 +770,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    938,
+/**/
     937,
 /**/
     936,