patch 8.1.0039: cannot easily delete lines in another buffer

Problem:    Cannot easily delete lines in another buffer.
Solution:   Add deletebufline().
diff --git a/src/version.c b/src/version.c
index caec4d6..0c804b9 100644
--- a/src/version.c
+++ b/src/version.c
@@ -762,6 +762,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    39,
+/**/
     38,
 /**/
     37,