Remove remnants of EVP_CIPHER-based AES_GCM cipher.

Those codepaths are never hit.

Change-Id: Ib6908ebe90ab667774785298fdc3f96acc4b50df
Reviewed-on: https://boringssl-review.googlesource.com/1693
Reviewed-by: Adam Langley <agl@google.com>
4 files changed