Do not use sha512-parisc for now, as it is subtly bugged - passes the sha
regress tests but causes tls ciphersuite using sha386 to fail; found the
hard way by henning@.
I can't see anything wrong in the generated assembly code yet, but building
a libcrypto with no assembler code but sha512_block_data_order() is enough
to trigger Henning's issue, so the bug lies there.
No ABI change; ok deraadt@