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
{
    
    
    
    static constexpr size_t DEST_LEN_BASE = 387;
    static constexpr size_t CERT_LEN_POS = 385;
    uint16_t cert_len;
    memcpy(&cert_len, &m_private_key.at(CERT_LEN_POS), sizeof(cert_len));
    cert_len = be16toh(cert_len);
    const size_t dest_len = DEST_LEN_BASE + cert_len;
    return Binary{m_private_key.begin(), m_private_key.begin() + dest_len};
}
void Session::CreateIfNotCreatedAlready()
{
    std::string errmsg;
    if (m_control_sock->IsConnected(errmsg)) {
        return;
    }
    const auto session_type = m_transient ? "transient" : "persistent";
    const auto session_id = GetRandHash().GetHex().substr(0, 10); 
    Log("Creating %s SAM session %s with %s", session_type, session_id, m_control_host.ToString());
    auto sock = Hello();
    if (m_transient) {