- Make tw_check_bits() static.
- Add MODULE_VERSION support.
- Fix ioctl path to use dma_alloc/free_coherent() instead of
  pci_alloc/free_consistent().
- Remove error variable from ioctl code causing confusion.
  retval defaults to -EFAULT, any copy_to/from_user() that
  returns non zero returns -EFAULT.
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>