The new DRBG API added the aforementioned #define. However, it is
used internally only and having it defined publicly does not serve
any purpose except causing potential version compatibility problems.

Fixes #7182
Reviewed-by: NMatt Caswell <matt@openssl.org>
Reviewed-by: NPaul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7190)

(cherry picked from commit c402e943cd0d748ca2a74a37caeccdfc59ce2870)