thin_trim usage does not match actual getopts settings

[tyll]

The thin_trim usage is:

thin_trim_cmd::usage(std::ostream &out) const
{
    out << "Usage: " << get_name() << " [options] {device|file}\n"
        << "Options:\n"
        << "  {--pool-inactive}\n"
        << "  {-h|--help}\n"
        << "  {-V|--version}" << endl;
}

but the getopt structure is different:

    const struct option longopts[] = {
        { "help", no_argument, NULL, 'h' },
        { "version", no_argument, NULL, 'V' },
        { "metadata-dev", required_argument, NULL, 0 },
        { "data-dev", required_argument, NULL, 1 },
        { "pool-inactive", no_argument, NULL, 2 },
        { NULL, no_argument, NULL, 0 }
    };

Also the manpage does not match the getopt options.