patch 9.1.0812: Coverity warns about dereferencing NULL ptr

Problem:  Coverity warns about dereferencing NULL ptr
          in check_colorcolumn()
Solution: verify that wp is not null before accessing it

related: #15914

Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/version.c b/src/version.c
index 226a05e..1f66cef 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    812,
+/**/
     811,
 /**/
     810,