Add brainpool curves to the tls default curves.

this fixes using the brainpool curves for TLS connections. ported from
openssl commit 469bcb0c24ba6360ca8f6f5660314fa11a8294f3.

see:

https://github.com/openssl/openssl/commit/469bcb0c24ba6360ca8f6f5660314fa11a8294f3