Enable the Integrity Measurement Architecture (IMA) for 4.14.x
and 4.15.x kernels. This pretty much uses the defaults except we
also enable INTEGRITY_ASYMMETRIC_KEYS and IMA_READ_POLICY. The
latter may be useful for debugging.
For s390x we also needed to enable TPM support.
Signed-off-by: Rolf Neugebauer <rolf.neugebauer@docker.com>
48251e8bcf