New loop now takes into account pages not physically contiguous.
Also some minor improvements, e.g. make the spin_lock used more locally,
reuse a group we had if we had one, etc.
This implements a skeleton setup function and call it on ioctl
Many missing points:
- missing pci mapping to make setup work
- no clear (passed to linux, so will likely bug out)
- missing locks/safe-guards
Conflicts:
kernel/Makefile.build.in
