Crash in JoystickImpl.cpp due to typo

[executionunit]

line 56 and 71 should test typeRef not ref.

If a joystick doesn't have a product Id it causes the application to exit with EXC_BAD_ACCESS. This can be recreated using a cheap PS2/N64 adapter on OS X.

[mantognini]

Indeed, that makes sense.

For reference: https://github.com/LaurentGomila/SFML/blob/master/src/SFML/Window/OSX/JoystickImpl.cpp#L52-L80