Maybe someday we'll be able to turn on that warning. (The EVP_CIPHER
hooks take size_t while the functions took long.)

Change-Id: Ic4da44efca9419a7f703e232d3f92638eb4ab37a
Reviewed-on: https://boringssl-review.googlesource.com/c/34084
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>