ppc/pnv: fix compile breakage on old gcc

PnvChip is defined twice and this can confuse old compilers :

  CC      ppc64-softmmu/hw/ppc/pnv_xscom.o
In file included from qemu.git/hw/ppc/pnv.c:29:
qemu.git/include/hw/ppc/pnv.h:60: error: redefinition of typedef ‘PnvChip’
qemu.git/include/hw/ppc/pnv_xscom.h:24: note: previous declaration of ‘PnvChip’ was here
make[1]: *** [hw/ppc/pnv.o] Error 1
make[1]: *** Waiting for unfinished jobs....

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
diff --git a/hw/ppc/pnv_lpc.c b/hw/ppc/pnv_lpc.c
index 00dbd8b..0e2117f 100644
--- a/hw/ppc/pnv_lpc.c
+++ b/hw/ppc/pnv_lpc.c
@@ -23,8 +23,9 @@
 #include "qapi/error.h"
 #include "qemu/log.h"
 
-#include "hw/ppc/pnv_lpc.h"
 #include "hw/ppc/pnv.h"
+#include "hw/ppc/pnv_lpc.h"
+#include "hw/ppc/pnv_xscom.h"
 #include "hw/ppc/fdt.h"
 
 #include <libfdt.h>