Disable the NetBSD-specific EFAULT requirements test in gettimeofday_err

FreeBSD doesn't specifically list this as a supported error, and in some
configurations/versions of FreeBSD, this test will segfault as the memory
address might be evaluated in userspace, instead of in kernel space like
in NetBSD.

MFC after: 1 week
Sponsored by: EMC / Isilon Storage Division