UBUNTU: SAUCE: LSM stacking: LSM: Manage file security blobs

UBUNTU: SAUCE: LSM stacking: LSM: Manage file security blobs

Move the management of file security blobs from the individual
security modules to the security infrastructure. The security modules
using file blobs have been updated accordingly. Modules are required
to identify the space they need at module initialization. In some
cases a module no longer needs to supply a blob management hook, in
which case the hook has been removed.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>