[PROJ] test failure with 6.3.0 geodtest

[Greg Troxel]

I have narrowed down the geodtest issue.  Thanks very much for your
earlier hint.

With respect to HAVE_C99_MATH, I have (munging the source) basically set
it to 1 in all respects, except that I am using the PROJ-provided
remquox implementation.  Then, tests pass.

In remquox, I added a call to remquo (OS-supplied), and looked for cases
with different output.  There are many, in *n (which I read the docs to
say is an output parameter).  Right now this points to a difference in
NetBSD's remqo from remquox, and it seems the NetBSD implementation is
out of spec, but the spec is slightly hard to follow.  I'll follow up
within NetBSD.