This was done in a mostly automated fashion.  I did it in three steps and then
rebased it into a single step which avoids repeatedly touching every file in
the tree.

The first step was a sed-based addition of the parent type to the subclass
registration functions.

The second step was another sed-based removal of subclass registration functions
while also adding virtual functions from the base class into a class_init
function as appropriate.

Finally, a python script was used to convert the DeviceInfo structures and
qdev_register_subclass functions to TypeInfo structures, class_init functions,
and type_register_static calls.

We are almost fully converted to QOM after this commit.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>