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
#include <utilsyserror.h>
#include <utilsystem.h>
#include <utilthread.h>
#include <utilthreadnames.h>
#include <utiltranslation.h>
#include <validation.h>
#include <validationinterface.h>
#include <walletinitinterface.h>
#include <algorithm>
#include <condition_variable>
#include <cstdint>
#include <cstdio>
#include <fstream>
#include <functional>
#include <set>
#include <string>
#include <thread>
#include <vector>
#ifndef WIN32
#include <cerrno>
#include <signal.h>
#include <sysstat.h>
#endif
#include <boostsignals2signal.hpp>
#if ENABLE_ZMQ
#include <zmqzmqabstractnotifier.h>
#include <zmqzmqnotificationinterface.h>
#include <zmqzmqrpc.h>
#endif
using kernel::DumpMempool;