This patch implements -march= and -mcpu= options to m68k's
assembler. It also adds a set of -m[no-]foo extension switches. In
addition I've rationalized the coldfire bfd_mach enumeration to work
along the lines of architectural features, rather than chip
numbering -- there's an ever increasing number of chips. I've kept
the old machine names and old assembler switches for compatibility.
This seems like a sensible proposal to me, however please ensure that
for the time being, the old-style command line options continue to be
supported. If you like, you could emit a warning and advise the user
of the new options. I really dislike seeing users left to work out
why their Makefiles have stopped working when they upgrade binutils.