PEM to DER decoder: Specify object type and data structure more consistently

PEM to DER decoder: Specify object type and data structure more consistently

The data structure wasn't given for recognised certificates or CRLs.
It's better, though, to specify it for those objects as well, so they
can be used to filter what actually gets decoded, which will be
helpful for our OSSL_STORE 'file:' scheme implementation.

Fixes #16224

Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/16466)