audit: Make audit_filter_syscall() return void

No invoker uses the return value of audit_filter_syscall().
So make it return void, and amend the comment of
audit_filter_syscall().
Signed-off-by: Yang Yang <yang.yang29@zte.com.cn>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
[PM: removed the changelog from the description]
Signed-off-by: Paul Moore <paul@paul-moore.com>

kernel/auditsc.c

@@ -799,12 +799,12 @@ static int audit_in_mask(const struct audit_krule *rule, unsigned long val)
 	return rule->mask[word] & bit;
 }
 
-/* At syscall entry and exit time, this filter is called if the
- * audit_state is not low enough that auditing cannot take place, but is
- * also not high enough that we already know we have to write an audit
- * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
+/* At syscall exit time, this filter is called if the audit_state is
+ * not low enough that auditing cannot take place, but is also not
+ * high enough that we already know we have to write an audit record
+ * (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
  */
-static enum audit_state audit_filter_syscall(struct task_struct *tsk,
+static void audit_filter_syscall(struct task_struct *tsk,
 					     struct audit_context *ctx,
 					     struct list_head *list)
 {
@@ -812,7 +812,7 @@ static enum audit_state audit_filter_syscall(struct task_struct *tsk,
 	enum audit_state state;
 
 	if (auditd_test_task(tsk))
-		return AUDIT_DISABLED;
+		return;
 
 	rcu_read_lock();
 	list_for_each_entry_rcu(e, list, list) {
@@ -821,11 +821,11 @@ static enum audit_state audit_filter_syscall(struct task_struct *tsk,
 				       &state, false)) {
 			rcu_read_unlock();
 			ctx->current_state = state;
-			return state;
+			return;
 		}
 	}
 	rcu_read_unlock();
-	return AUDIT_BUILD_CONTEXT;
+	return;
 }
 
 /*