Stable device identifier for evdev

Fix some small stuff found with Valgrind

Conflicts:
	Source/Core/Core/PowerPC/CachedInterpreter.cpp

Was using m_id insted of m_fd.
Also re-arrange the code so rumble effects always get deleted instead of
just on stop commands.

Using SDL_INIT_JOYSTICK implies SDL_INIT_EVENTS which installs a signal
handler for SIGINT and SIGTERM. There will be a way to prevent this in
2.0.4 but for now we'll need to handle SDL_QUIT.