staging: visorchipset driver to provide registration and other services

staging: visorchipset driver to provide registration and other services

The visorchipset module receives device creation and destruction
events from the Command service partition of s-Par, as well as
controlling registration of shared device drivers with the s-Par
driver core. The events received are used to populate other s-Par
modules with their assigned shared devices. Visorchipset is required
for shared device drivers to function properly. Visorchipset also
stores information for handling dump disk device creation during
kdump.

In operation, the visorchipset module processes device creation and
destruction messages sent by s-Par's Command service partition through
a channel. These messages result in creation (or destruction) of each
virtual bus and virtual device. Each bus and device is also associated
with a communication channel, which is used to communicate with one or
more IO service partitions to perform device IO on behalf of the
guest.

Signed-off-by: Ken Cox <jkc@redhat.com>
Cc: Ben Romer <sparmaintainer@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>