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
{
    KeyInfo result;
    
    size_t option_index = key.find('.');
    if (option_index != std::string::npos) {
        result.section = key.substr(0, option_index);
        key.erase(0, option_index + 1);
    }
    if (key.substr(0, 2) == "no") {
        key.erase(0, 2);
        result.negated = true;
    }
    result.name = key;
    return result;
}
/**
 * Interpret settings value based on registered flags.
 *
 * @param[in]   key      key information to know if key was negated
 * @param[in]   value    string value of setting to be parsed
 * @param[in]   flags    ArgsManager registered argument flags
 * @param[out]  error    Error description if settings value is not valid
 *
 * @return parsed settings value if it is valid, otherwise nullopt accompanied
 * by a descriptive error string
 */
static std::optional<util::SettingsValue> InterpretValue(const KeyInfo& key, const std::string* value,