The `make install` script, which most users would run via `sudo` to install into `/usr/local`, will use the current umask of the root user when creating certain files and directories. If one uses a restrictive umask by default (e.g. `umask 077`), this means that only the root user will be able to use the full Bitcoin package.

**Expected behavior**

The install script creates all directories and files, including man pages, etc., with permissions `644` / `755`.

**Actual behavior**

Certain folders are created using the default umask, e.g.:

- /usr/local/share/man/man1/
- /usr/local/lib/pkgconfig/
- [...]

This means that only root can access files in these folders and other users won't be able to read the man pages (for example).

**To reproduce**

```bash
$ ./autogen.sh
$ make
$ sudo -iu root
% umask 077
% make install
```

**System information**

OS: Linux
bitcoind version: HEAD
assert(util::SettingsSpan(*includes).last_negated());
                use_conf_file = false;
            }
        }
        if (use_conf_file) {
            std::string chain_id = GetChainName();
            std::vector<std::string> conf_file_names;
            auto add_includes = [&](const std::string& network, size_t skip = 0) {
                size_t num_values = 0;
                LOCK(cs_args);
                if (auto* section = util::FindKey(m_settings.ro_config, network)) {
                    if (auto* values = util::FindKey(*section, "includeconf")) {
                        for (size_t i = std::max(skip, util::SettingsSpan(*values).negated()); i < values->size(); ++i) {
                            conf_file_names.push_back((*values)[i].get_str());
                        }
                        num_values = values->size();
                    }
                }
                return num_values;
            };
            
            
            const size_t chain_includes = add_includes(chain_id);
            const size_t default_includes = add_includes({});
            for (const std::string& conf_file_name : conf_file_names) {
                std::ifstream conf_file_stream{GetConfigFile(fs::PathFromString(conf_file_name))};
                if (conf_file_stream.good()) {
                    if (!ReadConfigStream(conf_file_stream, conf_file_name, error, ignore_invalid_keys)) {
                        return false;