tools: drop unused field in struct

check_seapp at one point in time switch from a home implementation
of a hash table to using GLIBC search.h routines. A struct in one
of the fields was never removed during this transition.

Change-Id: I65c028103ffe90fa52e0b3c9fce28124ed9c7ff9

tools/check_seapp.c

@@ -102,7 +102,6 @@ struct rule_map {
 	char *key; /** key value before hashing */
 	int length; /** length of the key map */
 	int lineno; /** Line number rule was encounter on */
-	rule_map *next; /** next pointer used in hash table for chaining on collision */
 	key_map m[]; /** key value mapping */
 };