patch 8.2.4267: unused entry in keymap enum

Problem:    Unused entry in keymap enum.
Solution:   Remove the entry.
diff --git a/src/version.c b/src/version.c
index ca506ad..382c84a 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4267,
+/**/
     4266,
 /**/
     4265,