Don't leave stale errors on queue if DSO_dsobyaddr() fails

The init code uses DSO_dsobyaddr() to leak a reference to ourselves to
ensure we remain loaded until atexit() time. In some circumstances that
can fail and leave stale errors on the error queue.

Fixes #3372

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3383)