doc: fix mistake in NetBSD notes
doc: fix mistake in NetBSD notes

It's 32-bit binaries that fail for reasons unknown on 64-bit kernels.

Change-Id: Ib410af0491160e3ed8d32118966142516123db2c
Reviewed-on: https://go-review.googlesource.com/82655
Reviewed-by: Andrew Bonventre <682ad9f487f614f19e8b7cc5d340bdc8e1c1b128@golang.org>

Cofyc/go,josharian/go,josharian/go,akutz/go,akutz/go,nawawi/go,akutz/go,nawawi/go,Cofyc/go,josharian/go,golang/go,codestation/go,cloudflare/go,codestation/go,cloudflare/go,cloudflare/go,nawawi/go,josharian/go,CAFxX/go,akutz/go,cloudflare/go,CAFxX/go,golang/go,golang/go,codestation/go,akutz/go,CAFxX/go,golang/go,Cofyc/go,josharian/go,akutz/go,akutz/go,Cofyc/go,nawawi/go,josharian/go,Cofyc/go,akutz/go,nawawi/go,cloudflare/go,golang/go,CAFxX/go,codestation/go,Cofyc/go,nawawi/go,cloudflare/go,josharian/go,josharian/go,cloudflare/go,nawawi/go,codestation/go,CAFxX/go,cloudflare/go,Cofyc/go,golang/go,codestation/go,codestation/go,nawawi/go,golang/go,codestation/go,christopher-henderson/Go,CAFxX/go,CAFxX/go,CAFxX/go,Cofyc/go,golang/go