Incorrect detection of MMX support in Intel Family 5 CPU's

[Torbjörn Granlund]

Thanks for tracing your crashes to GMP and thanks for reporting it to
us.  You demonstrate a fragility in our CPU detection.

Please try these patches:

https://gmplib.org/repo/gmp/raw-rev/cd5e58236267
https://gmplib.org/repo/gmp/raw-rev/4117847f9e8b

If you can make both a plain build and one with --enable-fat, that would
be great.  Please report back success/failure by following up to this
message.

-- 
Torbjörn
Please encrypt, key id 0xC8601622