This change causes cipher_test to test the EVP cipher interfaces with
various chunk sizes and adds a couple of large tests of GCM. This is
sufficient to uncover the issue that would have been caused by a3d9528e,
had the AVX code been enabled.
Change-Id: I58d4924c0bcd11a0999c24a0fb77fc5eee71130f
Reviewed-on: https://boringssl-review.googlesource.com/7192
Reviewed-by: David Benjamin <davidben@google.com>