pc: Move {above,below}_4g_mem_size variables to PCMachineState
This will make the info readily available for the other initialization
functions, and will allow us to simplify their argument list.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>