My tty+X11 binary was letting me see and modify status highlights under
X11 even though they don't do anything. Options parsing has to accept
them since we don't know which interface will be chosen, but interactive
option handling does know and shouldn't show inappropriate options.
initoptions_finish() should probably we validating all the wc and wc2
options, but I only added a check for trying to enable statushilites
when they're unavailable.