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.

src/version.c

@@ -794,6 +794,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    261,
 /**/
     260,
 /**/