[ 031/101] staging: comedi: amplc_dio200: fix possible NULL deref during detach

3.6-stable review patch. If anyone has any objections, please let me know. -- From: Ian Abbott commit dfb2540e91e1f63765bc3ff497ad0b714d774261 upstream. `dio200_detach()` is called by the comedi core to clean up if either `dio200_attach()` or `dio200_attach_pci()` return an

[ 031/101] staging: comedi: amplc_dio200: fix possible NULL deref during detach

3.6-stable review patch. If anyone has any objections, please let me know. -- From: Ian Abbott abbo...@mev.co.uk commit dfb2540e91e1f63765bc3ff497ad0b714d774261 upstream. `dio200_detach()` is called by the comedi core to clean up if either `dio200_attach()` or