UBUNTU: SAUCE: Stacking v38: LSM: Use lsmblob in security_cred_getsecid

UBUNTU: SAUCE: Stacking v38: LSM: Use lsmblob in security_cred_getsecid

BugLink: https://bugs.launchpad.net/bugs/2012136
Change the security_cred_getsecid() interface to fill in a
lsmblob instead of a u32 secid. The associated data elements
in the audit sub-system are changed from a secid to a lsmblob
to accommodate multiple possible LSM audit users.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: linux-integrity@vger.kernel.org
Cc: linux-audit@redhat.com
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>