[krbdev.mit.edu #1849] redhat opteron patch: 1.2.7 needs casts, headers

[Ken Raeburn via RT]

I expect we won't be fixing up 1.2.7 for opteron, but to get it on the
record....

>From Nalin Dahyabhai:

[...]
I'm not sure if you are planning on updating 1.2 for Opteron boxes, but
the 1.2 base has problems due to the size mismatch when the value
returned by a function which returns a pointer is then passed to a
varargs function.  If it's implicitly defined due to a missing header
inclusion, the compiler will compile code to expect an int instead of a
pointer, and we end up passing garbage data to functions like sprintf().
All of the instances I saw that definitely needed patching in 1.2 were
already fixed in 1.3 (where -Wall, which is used during the build,
includes -Wimplicit, which flags most these as warnings).  I'm attaching
a patch for 1.2.7 to fix the ones I expect to cause errors.  Save for
the tests which I expect to fail due to the removal of des3 from krb4,
the test suite here also looks good.

On both, config.guess and config.sub needed updating so that configure
wouldn't bail out because 'x86_64-*-linux' wasn't recognized, but I
expect that'll take care of itself eventually.