CFLAGS is a user variable, extracted from the environment at configure time
and settable by the user at build time. We must not override this variable.
Get rid of almost all uses of these definitions. They're still defined for
delinquent out-of-tree drivers, and also for the Mesa build. As well as
for miinitext.c. But largely gone.
- Use x86emu on Solaris instead of vm86
- Better per-OS control over which xf86Kbd*.c and *Pci.c files to build
- Set various #defines to be defined or not on Solaris as needed
