(CPP_CPU_ARCH_SPEC): Handle -march=...

(TARGET_OPTIONS): Add arch= and fp=.  Delete fpe=.
(enum processor_type): Add PROCESSOR_NONE, for use in all_procs table.
(FP_DEFAULT): Default floating point architecture for generic
back-end.
(PREDICATE_CODES): Add f_register_operand.

From-SVN: r14460