Replumbing: Add a mechanism to pre-populate the provider store

Replumbing: Add a mechanism to pre-populate the provider store

OpenSSL will come with a set of well known providers, some of which
need to be accessible from the start.  These are typically built in
providers, or providers that will work as fallbacks.

We do this when creating a new provider store, which means that this
will happen in every library context, regardless of if it's the global
default one, or an explicitely created one.

We keep the data about the known providers we want to make accessible
this way in crypto/provider_predefined.h, which may become generated.
For now, though, we make it simple and edited manually.

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/8480)