patch 8.2.5115: search timeout is overrun with some patterns

Problem:    Search timeout is overrun with some patterns.
Solution:   Check for timeout in more places.  Make the flag volatile and
            atomic.  Use assert_inrange() to see what happened.

src/version.c

@@ -734,6 +734,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    5115,
 /**/
     5114,
 /**/