runtime: use quiet NaNs in softfloat implementation
runtime: use quiet NaNs in softfloat implementation

Update #37455

Change-Id: Ieac0823aa398d73187c009037be15ba34c84f3d9
Reviewed-on: https://go-review.googlesource.com/c/go/+/221433
Run-TryBot: Emmanuel Odeke <277f8eaa8c7dfbc55c17bf5e30561c1a9c45c569@gmail.com>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Cherry Zhang <d62e63aa42ce272d7b6a5055d97e942b33a34679@google.com>

golang/go,akutz/go,akutz/go,golang/go,cloudflare/go,CAFxX/go,golang/go,golang/go,golang/go,golang/go,akutz/go,nawawi/go,golang/go,nawawi/go,cloudflare/go,nawawi/go,CAFxX/go,cloudflare/go,nawawi/go,CAFxX/go,cloudflare/go,CAFxX/go,cloudflare/go,akutz/go,nawawi/go,nawawi/go,CAFxX/go,cloudflare/go,akutz/go,akutz/go,akutz/go,cloudflare/go,cloudflare/go,CAFxX/go,golang/go,akutz/go,nawawi/go,CAFxX/go,nawawi/go,CAFxX/go