libc: fix strtold NaN representation on riscv

[siva]

Summary

Regenerate gd_qnan.h on riscv using the qnan.c
config tool found in contrib/gdtoa.

This fixes the following tests in CI:
https://ci.freebsd.org/job/FreeBSD-main-riscv64-test/16612/testReport/lib.libc.stdio/scanfloat_test/infinities_and_nans/
https://ci.freebsd.org/job/FreeBSD-main-riscv64-test/16612/testReport/lib.libc.stdlib/strtod_test/strtold_nan/

[jrtc27]

Hm, seems the current version is the same as the arm file, and now it's the same as the aarch64 one? I'm guessing copying from arm is how this came to be...

Please trim the URLs from the commit message and just mention the test names though, they're a bit long and cumbersome otherwise

[br]

In D57405#1315493, @jrtc27 wrote:

Hm, seems the current version is the same as the arm file, and now it's the same as the aarch64 one? I'm guessing copying from arm is how this came to be...

Looks like arm's gd_qnan.h was also regenerated recently. So not sure where I got this one from :)