memory: Constify IOMMUTLBEvent in memory_region_notify_iommu_one()

@event access is read-only.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <20240612132532.85928-2-philmd@linaro.org>

include/exec/memory.h

@@ -1852,7 +1852,7 @@ void memory_region_notify_iommu(IOMMUMemoryRegion *iommu_mr,
  *         range.
  */
 void memory_region_notify_iommu_one(IOMMUNotifier *notifier,
-                                    IOMMUTLBEvent *event);
+                                    const IOMMUTLBEvent *event);
 
 /**
  * memory_region_unmap_iommu_notifier_range: notify a unmap for an IOMMU

system/memory.c

@@ -2006,9 +2006,9 @@ void memory_region_unregister_iommu_notifier(MemoryRegion *mr,
 }
 
 void memory_region_notify_iommu_one(IOMMUNotifier *notifier,
-                                    IOMMUTLBEvent *event)
+                                    const IOMMUTLBEvent *event)
 {
-    IOMMUTLBEntry *entry = &event->entry;
+    const IOMMUTLBEntry *entry = &event->entry;
     hwaddr entry_end = entry->iova + entry->addr_mask;
     IOMMUTLBEntry tmp = *entry;