crashes on slow devices when obtaining the control socket's file descriptor

Testing with an ancient Samsung Galaxy S (!), I saw nullpointer exceptions, when [attempting to obtain the filedescriptor of the control socket](https://github.com/guardianproject/tor-android/blob/c43cea7492903d3b8fd9544a77f650e642bbe6ae/tor-android-binary/src/main/java/org/torproject/jni/TorService.java#L293)
```
FileDescriptor controlSocketFd = prepareFileDescriptor(getControlSocket(TorService.this).getAbsolutePath());
```
I haven't tested that fix https://github.com/guardianproject/tor-android/pull/76, but what I did is to [iterate over that line with a little delay](https://0xacab.org/leap/android_libs/tor-android/-/blob/main/tor-android-binary/src/main/java/org/torproject/jni/TorService.java#L350). It's not well designed, but it fixed my real-world problem and reduced the crash rate.

Feel free to close this issue, might just be an idea.