This is a patch for qemu to allow using PCI devices on the host machine
from within the guest machine (for now, only as long as Linux is the
host OS). This is in order to facilitate the easy reverse engineering of
PCI devices.

TODO:
 o Implement poll method and sigio for irq signals
 o Allow a non SA_SHARED IRQ to share provided it is last on the call
   chain
 o Write usermode PCI driver library and tools
 o Fast logging support of data
 o Support for AGP cards with GART proxying
 o Support PCI-DMA -
   o get it working with linux guest patches first
   o then investigate patching host to give qemu the bottom few MB of RAM
     identity mapped in to the process space
 o Lock the PCI device when in use
 o PCI network server