This refactors OSSL_LIB_CTX to avoid using CRYPTO_EX_DATA. The assorted
objects to be managed by OSSL_LIB_CTX are hardcoded and are initialized
eagerly rather than lazily, which avoids the need for locking on access
in most cases.
Fixes#17116.
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/17881)