Before RFC 7539 we had a ChaCha20-Poly1305 cipher suite that had a 64/64
nonce/counter split (as DJB's original ChaCha20 did). RFC 7539 changed
that to 96/32 and we've supported both for some time.
This change removes the old version and the TLS cipher suites that used
it.
BUG=chromium:682816
Change-Id: I2345d6db83441691fe0c1ab6d7c6da4d24777849
Reviewed-on: https://boringssl-review.googlesource.com/13203
Reviewed-by: Adam Langley <agl@google.com>
Adam Langley