CRED: Separate task security context from task_struct

Separate the task security context from task_struct.  At this point, the
security data is temporarily embedded in the task_struct with two pointers
pointing to it.

Note that the Alpha arch is altered as it refers to (E)UID and (E)GID in
entry.S via asm-offsets.

With comment fixes Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com>

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/kernel/tsacct.c b/kernel/tsacct.c
index 8ebcd85..6d1ed07 100644
--- a/kernel/tsacct.c
+++ b/kernel/tsacct.c
@@ -53,8 +53,8 @@
 		stats->ac_flag |= AXSIG;
 	stats->ac_nice	 = task_nice(tsk);
 	stats->ac_sched	 = tsk->policy;
-	stats->ac_uid	 = tsk->uid;
-	stats->ac_gid	 = tsk->gid;
+	stats->ac_uid	 = tsk->cred->uid;
+	stats->ac_gid	 = tsk->cred->gid;
 	stats->ac_pid	 = tsk->pid;
 	rcu_read_lock();
 	stats->ac_ppid	 = pid_alive(tsk) ?