crypto: algboss - optimize registration of internal algorithms

Since algboss always skips testing of algorithms with the
CRYPTO_ALG_INTERNAL flag, there is no need to go through the dance of
creating the test kthread, which creates a lot of overhead.  Instead, we
can just directly finish the algorithm registration, like is now done
when self-tests are disabled entirely.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>