patch 8.1.0261: Coverity complains about a negative array index

Problem:    Coverity complains about a negative array index.
Solution:   When qf_id2nr() cannot find the list then don't set qf_curlist.
diff --git a/src/version.c b/src/version.c
index 962d173..9e2ee2e 100644
--- a/src/version.c
+++ b/src/version.c
@@ -795,6 +795,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    261,
+/**/
     260,
 /**/
     259,