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
{
#ifndef WIN32
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    if (file) {
        fsync(fileno(file));
        fclose(file);
    }
#endif
}
bool TruncateFile(FILE *file, unsigned int length) {
#if defined(WIN32)
    return _chsize(_fileno(file), length) == 0;
#else
    return ftruncate(fileno(file), length) == 0;
#endif
}
/**
 * this function tries to raise the file descriptor limit to the requested number.
 * It returns the actual file descriptor limit (which may be more or less than nMinFD)
 */
int RaiseFileDescriptorLimit(int nMinFD) {