x86: Fix the flag handling code in FABS and FCHS

This changeset fixes two problems in the FABS and FCHS
implementation. First, the ISA parser expects the assignment in
flag_code to be a pure assignment and not an and-assignment, which
leads to the isa_parser omitting the misc reg update. Second, the FCHS
and FABS macro-ops don't set the SetStatus flag, which means that the
default micro-op version, which doesn't update FSW, is executed.

x86: implement fabs, fchs instructions

copyright: Change HP copyright on x86 code to be more friendly

X86: Put in stubs for x87, 64 bit and 128 bit SIMD instruction microcode.