NativeCrypto: compatibility with OpenSSL
NativeCrypto: compatibility with OpenSSL

OpenSSL has different definitions for the ECDSA functions which causes
compilation errors when we're being strict. Sprinkle in some more #ifdef
to allow compilation for both.

Change-Id: Iafe3799289980fdf7862a861b2aee4517dbd869a

google/conscrypt,google/conscrypt,google/conscrypt,google/conscrypt,google/conscrypt,google/conscrypt