Log Message:
python313: Extend NetBSD "fix" to SunOS too.

It's somewhat odd that this is being seen on all pkgsrc platforms, e.g. here
on Linux too:

  \ 
https://us-central.manta.mnx.io/pkgsrc/public/reports/Linux/el9/trunk/x86_64/20241019.1600/python313-3.13.0/build.log

This suggests we are doing something actively harmful somewhere else in our
package as there's no way upstream would ship a broken python 3.13 on Linux,
but I don't have time to debug that right now, nor test the "fix" on Linux.