Elliptic curve implementation sanity check

[bbrumley@xxxxxxxxx (Billy Brumley)]

> * On architectures where nistz256 is not implemented, a default
>   OpenSSL build will use the generic Weierstrass implementation.  I
>   haven't been able to determine whether there are significant timing
>   channels in that implementation.

Researches have been beating up "the generic Weierstrass
implementation" since 2009.

BBB