patch 8.2.0934: lhelpgrep twice in help window doesn't jump to the help topic

Problem:    Running lhelpgrep twice in a help window doesn't jump to the help
            topic.
Solution:   Check whether any window with the location list is present.
            (Yegappan Lakshmanan, closes #6215)

src/version.c

@@ -754,6 +754,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    934,
 /**/
     933,
 /**/