TOMOYO: Fix interactive judgment functionality.

Commit 17fcfbd9 "TOMOYO: Add interactive enforcing mode." introduced ability
to query access decision using userspace programs. It was using global PID for
reaching policy configuration of the process. However, use of PID returns stale
policy configuration when the process's subjective credentials and objective
credentials differ. Fix this problem by allowing reaching policy configuration
via query id.

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