Bug in ax_gcc_archflag.m4

Not sure who should get this, since there's no contact information in
the file for the current maintainer, so...

This script sets a CPU specific optimization flag for gcc.

I have a Westmere Intel CPU that the script detects as a Sandybridge,
which will cause a crash when gcc tries to use instructions the latter
has but the former doesn't.

The cpu id 1 string for the computer in question:

206d7:2200800:83b82203:789fbff

This matches a case pattern for Sandybridge, but not the Westmere it
is. I don't know enough about cpuid guts and how they map to the
different cpu architectures and sub-versions to actually fix it, though.

-- 
Shawn Wagner
[email protected]