staging/comedi: Use comedi_pci_auto_unconfig directly for pci_driver.remove

(Almost) all comedi pci drivers have some wrapper for their
pci_driver.remove function which simply calls comedi_pci_auto_unconfig
which has the same function prototype as the wrapper.

-> we can remove these wrappers and call comedi_pci_auto_unconfig
directly. This removes a lot some boilerplate code and saves some bytes.

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>