autoconf: remove uss from configure summary

autoconf: remove uss from configure summary

Commit 00a33b26d74aa067086ddc340efb82184715857f (uss: always build uss)
made the uss build unconditional. Remove it from the list of optional
items in the configure summary.

Reviewed-on: https://gerrit.openafs.org/13004
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>
(cherry picked from commit 85e9db22b265f9bb3745246fea3a07158b8a8c0e)

Change-Id: I345752f0739edc3d621b39a50157adb23923e256
Reviewed-on: https://gerrit.openafs.org/13111
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Michael Meffie <mmeffie@sinenomine.net>
Reviewed-by: Andrew Deason <adeason@sinenomine.net>
Reviewed-by: Joe Gorse <jhgorse@gmail.com>
Reviewed-by: Marcio Brito Barbosa <mbarbosa@sinenomine.net>
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>