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
: m_control_host{control_host},
      m_interrupt{interrupt},
      m_control_sock{std::make_unique<Sock>(INVALID_SOCKET)},
      m_transient{true}
{
}
Session::~Session()
{
    LOCK(m_mutex);
    Disconnect();
}
bool Session::Listen(Connection& conn)
{
    try {
        LOCK(m_mutex);
        CreateIfNotCreatedAlready();
        conn.me = m_my_addr;
        conn.sock = StreamAccept();
        return true;
    } catch (const std::runtime_error& e) {
        Log("Error listening: %s", e.what());
        CheckControlSock();
    }
    return false;
}
bool Session::Accept(Connection& conn)