Fix build failure.

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@2545 c046a42c-6fe2-441c-8c8c-71466251a162

vl.h

@@ -859,9 +859,11 @@ enum {
     OPENPIC_EVT_DEBUG,   /* Inconditional debug event */
     OPENPIC_EVT_RESET,   /* Core reset event          */
 };
+struct CPUPPCState;
 void openpic_set_irq(void *opaque, int n_IRQ, int level);
 openpic_t *openpic_init (PCIBus *bus, SetIRQFunc *set_irq,
-                         int *pmem_index, int nb_cpus, CPUPPCState **envp);
+                         int *pmem_index, int nb_cpus,
+                         struct CPUPPCState **envp);
 
 /* heathrow_pic.c */
 typedef struct HeathrowPICS HeathrowPICS;