Use more upstream NetBSD, and update those things that were already NetBSD.
Note that unlike bionic, the upstream-netbsd directory isn't pristine; we have
changes marked by __ANDROID__.
Bug: 16493461
(cherry picked from commit fd4c6b0a3a)
Change-Id: I53267edaac0b92ad062a5df0f3201e3952eb084e