TOMOYO: Fix exception policy read failure.

Due to wrong initialization, "cat /sys/kernel/security/tomoyo/exception_policy"
returned nothing.

Signed-off-by: Kentaro Takeda <takedakn@nttdata.co.jp>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Toshiharu Harada <haradats@nttdata.co.jp>
Signed-off-by: James Morris <jmorris@namei.org>

security/tomoyo/domain.c

@@ -376,7 +376,7 @@ int tomoyo_write_domain_keeper_policy(char *data, const bool is_not,
 bool tomoyo_read_domain_keeper_policy(struct tomoyo_io_buffer *head)
 {
 	struct list_head *pos;
-	bool done = false;
+	bool done = true;
 
 	down_read(&tomoyo_domain_keeper_list_lock);
 	list_for_each_cookie(pos, head->read_var2,