The free callbacks can assume their inputs are non-NULL. They're only
called from BIOs of the corresponding method, which means the BIO must
exist. Also new callbacks that leave everything zero-initialized are
no-ops and can be omitted.
This removes the weird thing where the built-in free functions were
fallible. Although the int return is still necessary for compatibility
with external BIOs.
Change-Id: I91e2101efc7c77c703cb649df1490bc9f515f0fd
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/48846
Reviewed-by: Adam Langley <agl@google.com>
David Benjamin
Adam Langley