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
{
    return std::thread::hardware_concurrency();
}
int64_t GetStartupTime()
{
    return nStartupTime;
}
fs::path AbsPathForConfigVal(const fs::path& path, bool net_specific)
{
    if (path.is_absolute()) {
        return path;
    }
    return fsbridge::AbsPathJoin(net_specific ? gArgs.GetDataDirNet() : gArgs.GetDataDirBase(), path);
}
void ScheduleBatchPriority()
{
#ifdef SCHED_BATCH
    const static sched_param param{};
    const int rc = pthread_setschedparam(pthread_self(), SCHED_BATCH, &param);
    if (rc != 0) {
        LogPrintf("Failed to pthread_setschedparam: %s\n", SysErrorString(rc));
    }
#endif
}
namespace util {
#ifdef WIN32
WinCmdLineArgs::WinCmdLineArgs()