rgw/sse-s3: save sse attributes in req_state->crypt_attribute_map

rgw/sse-s3: save sse attributes in req_state->crypt_attribute_map

req_state->crypt_attribute_map to save sse-s3 cryptographic attributes
this is not quite a duplicate of x_meta_map because I think some of
        of its uses conflict with sse-s3. (for instance, bucketencryption vs. signatures)

Signed-off-by: Marcus Watts <mwatts@redhat.com>