Revert "Modify test/afalgtest to fail if the afalg engine couldn't be loaded"

It turns out that even if you successfully build the engine, it might
not load properly, so we cannot make the test program fail for it.

See the message in commit 25b9d11c

This reverts commit 227a1e3f

.

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5276)