lsm: rename ordered_lsm_init() to lsm_init_ordered()

lsm: rename ordered_lsm_init() to lsm_init_ordered()

The new name more closely fits the rest of the naming scheme in
security/lsm_init.c.  This patch also adds a trivial comment block to
the top of the function.

Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: John Johansen <john.johhansen@canonical.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>