OSSL_STORE 'file:' scheme: Set input structure for certificates and CRLs

OSSL_STORE 'file:' scheme: Set input structure for certificates and CRLs

When the user expects to load a certificate or a CRL through the
OSSL_STORE loading function, the 'file:' implementation sets the
corresponding structure names in the internal decoder context.
This is especially geared for PEM files, which often contain a mix of
objects, and password prompting should be avoided for objects that
need them, but aren't what the caller is looking for.

Fixes #16224

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