KVM: Split QEMUMachine typedef into separate header

Older gcc versions (such as the one in SLES11) get confused when you declare
a typedef on the same struct twice.

To work around that limitation, let's extract the QEMUMachine typedef into a
separate header file that is guarded by preprocessor duplicate include checks.

This fixes the following type of compile errors for me:

  In file included from vl.c:125:
  include/hw/xen/xen.h:39: error: redefinition of typedef "QEMUMachine"
  include/sysemu/kvm.h:155: error: previous declaration of "QEMUMachine" was here

Signed-off-by: Alexander Graf <agraf@suse.de>

include/hw/boards.h

@@ -4,10 +4,9 @@
 #define HW_BOARDS_H
 
 #include "sysemu/blockdev.h"
+#include "sysemu/qemumachine.h"
 #include "hw/qdev.h"
 
-typedef struct QEMUMachine QEMUMachine;
-
 typedef struct QEMUMachineInitArgs {
     const QEMUMachine *machine;
     ram_addr_t ram_size;

include/hw/xen/xen.h

@@ -10,6 +10,7 @@
 
 #include "hw/irq.h"
 #include "qemu-common.h"
+#include "sysemu/qemumachine.h"
 
 /* xen-machine.c */
 enum xen_mode {

include/sysemu/kvm.h

@@ -18,6 +18,7 @@
 #include "config-host.h"
 #include "qemu/queue.h"
 #include "qom/cpu.h"
+#include "sysemu/qemumachine.h"
 
 #ifdef CONFIG_KVM
 #include <linux/kvm.h>

include/sysemu/qemumachine.h

@@ -0,0 +1,16 @@
+/*
+ * QEMU Machine typedef
+ *
+ * Copyright Alexander Graf <agraf@suse.de>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#ifndef QEMUMACHINE_H
+#define QEMUMACHINE_H
+
+typedef struct QEMUMachine QEMUMachine;
+
+#endif /* !QEMUMACHINE_H */

include/sysemu/qtest.h

@@ -16,6 +16,7 @@
 
 #include "qemu-common.h"
 #include "qapi/error.h"
+#include "sysemu/qemumachine.h"
 
 extern bool qtest_allowed;
 

kvm-stub.c

@@ -14,6 +14,7 @@
 #include "hw/hw.h"
 #include "cpu.h"
 #include "sysemu/kvm.h"
+#include "sysemu/qemumachine.h"
 
 #ifndef CONFIG_USER_ONLY
 #include "hw/pci/msi.h"