Re: src/include/utils/float.h comment one link stable

I wrote:
> David Rowley <dgrowleyml@gmail.com> writes:
>> I'd be happy for someone else to
>> continue. I'm a bit hesitant due to the "#if defined(NAN) &&
>> !(defined(__NetBSD__) && defined(__mips__))", which are systems I have
>> little knowledge of.

> Fair enough, I'll take responsibility for that bit.  Might as well
> wait to see how the BF likes the INFINITY change, though.

The three active Windows animals all seem happy with INFINITY,
ditto Solaris and derivatives.  So I'll proceed with changing
the NAN support similarly.

As a side note: I realized while researching the commit history
that there are copies of get_float8_infinity and get_float8_nan
in src/interfaces/ecpg/ecpglib/data.c.  Will take care of those
while at it, and maybe put in a cross-reference to help the
next hacker.

            regards, tom lane