machine: move dies from X86MachineState to CpuTopology

In order to make SMP configuration a Machine property, we need a getter as
well as a setter.  To simplify the implementation put everything that the
getter needs in the CpuTopology struct.

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210617155308.928754-7-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/include/hw/boards.h b/include/hw/boards.h
index 3d55d2b..87ae5cc 100644
--- a/include/hw/boards.h
+++ b/include/hw/boards.h
@@ -282,6 +282,7 @@
  */
 typedef struct CpuTopology {
     unsigned int cpus;
+    unsigned int dies;
     unsigned int cores;
     unsigned int threads;
     unsigned int sockets;