TOMOYO: Fix quota check.

Commit d74725b9 "TOMOYO: Use callback for updating entries." broke
tomoyo_domain_quota_is_ok() by counting deleted entries. It needs to
count non-deleted entries.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>