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/include/linux/securebits.h b/include/linux/securebits.h
index 92f09bd..6d38949 100644
--- a/include/linux/securebits.h
+++ b/include/linux/securebits.h
@@ -32,7 +32,7 @@
    setting is locked or not. A setting which is locked cannot be
    changed from user-level. */
 #define issecure_mask(X)	(1 << (X))
-#define issecure(X)		(issecure_mask(X) & current->securebits)
+#define issecure(X)		(issecure_mask(X) & current->cred->securebits)
 
 #define SECURE_ALL_BITS		(issecure_mask(SECURE_NOROOT) | \
 				 issecure_mask(SECURE_NO_SETUID_FIXUP) | \