spapr: Move typedef SpaprMachineState to spapr.h

spapr: Move typedef SpaprMachineState to spapr.h

Move the typedef from spapr_irq.h to spapr.h, and use "struct
SpaprMachineState" in the spapr_*.h headers (to avoid circular
header dependencies).

This will make future conversion to OBJECT_DECLARE* easier.

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Tested-By: Roman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20200825192110.3528606-28-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>