pvfb: Split mouse and keyboard into separate devices.

pvfb: Split mouse and keyboard into separate devices.

This patch creates two separate input devices for keyboard and mouse
events.  The reason for this is to separate them in the linux input
layer and allow them being routed different ways.

Use case:  Configure the X-Server like this to get the mouse
events directly from the linux input layer, which has the major
advantage that absolute coordinates work correctly:

Section "InputDevice"
  Driver       "evdev"
  Identifier   "Mouse"
  Option       "Device" "/dev/input/event<nr>"
EndSection

This makes the keyboard stop working though in case mouse and
keyboard events are coming through the same input device, at least
with older Xorg (6.9) versions.

Signed-off-by: Gerd Hoffmann <kraxel@suse.de>
Assign fake pci product identifiers down from 0xffff. This may help
clarify that the devices are not actually PCI. Also it reduces
probability of accidental conflict if further real PCI assignments
occur in future (0x0002, 0x0003, ... would be obvious next identifiers
to allocate).

Signed-off-by: Keir Fraser <keir@xensource.com>