upstream: Don't try to use sudo inside sshd log wrapper.

upstream: Don't try to use sudo inside sshd log wrapper.

We still need to check if we're using sudo since we don't want to chown
unecessarily, as on some platforms this causes an error which pollutes
stderr. We also don't want to unnecessarily invoke sudo, since it's
running in the context of the proxycommand, on *other* platforms it
may not be able to authenticate, and if we're using SUDO then it should
already be privileged.

OpenBSD-Regress-ID: 70d58df7503db699de579a9479300e5f3735f4ee