Add const qualifier to handles where possible

This mirrors the Vulkan specification where handles are often passed with a const qualifier
diff --git a/src/vk_mem_alloc.h b/src/vk_mem_alloc.h
index 7e70a9e..e7aa487 100644
--- a/src/vk_mem_alloc.h
+++ b/src/vk_mem_alloc.h
@@ -3361,7 +3361,7 @@
     It is safe to pass allocations that are in the lost state - they are ignored.

     All allocations not present in this array are considered non-moveable during this defragmentation.

     */

-    VmaAllocation* pAllocations;

+    const VmaAllocation* pAllocations;

     /** \brief Optional, output. Pointer to array that will be filled with information whether the allocation at certain index has been changed during defragmentation.

 

     The array should have `allocationCount` elements.

@@ -3386,7 +3386,7 @@
     Using this array is equivalent to specifying all allocations from the pools in `pAllocations`.

     It might be more efficient.

     */

-    VmaPool* pPools;

+    const VmaPool* pPools;

     /** \brief Maximum total numbers of bytes that can be copied while moving allocations to different places using transfers on CPU side, like `memcpy()`, `memmove()`.

     

     `VK_WHOLE_SIZE` means no limit.

@@ -3558,7 +3558,7 @@
 */

 VMA_CALL_PRE VkResult VMA_CALL_POST vmaDefragment(

     VmaAllocator allocator,

-    VmaAllocation* pAllocations,

+    const VmaAllocation* pAllocations,

     size_t allocationCount,

     VkBool32* pAllocationsChanged,

     const VmaDefragmentationInfo *pDefragmentationInfo,

@@ -7123,10 +7123,10 @@
         VmaDefragmentationStats* pStats);

     ~VmaDefragmentationContext_T();

 

-    void AddPools(uint32_t poolCount, VmaPool* pPools);

+    void AddPools(uint32_t poolCount, const VmaPool* pPools);

     void AddAllocations(

         uint32_t allocationCount,

-        VmaAllocation* pAllocations,

+        const VmaAllocation* pAllocations,

         VkBool32* pAllocationsChanged);

 

     /*

@@ -14225,7 +14225,7 @@
     }

 }

 

-void VmaDefragmentationContext_T::AddPools(uint32_t poolCount, VmaPool* pPools)

+void VmaDefragmentationContext_T::AddPools(uint32_t poolCount, const VmaPool* pPools)

 {

     for(uint32_t poolIndex = 0; poolIndex < poolCount; ++poolIndex)

     {

@@ -14262,7 +14262,7 @@
 

 void VmaDefragmentationContext_T::AddAllocations(

     uint32_t allocationCount,

-    VmaAllocation* pAllocations,

+    const VmaAllocation* pAllocations,

     VkBool32* pAllocationsChanged)

 {

     // Dispatch pAllocations among defragmentators. Create them when necessary.

@@ -17879,7 +17879,7 @@
 VMA_CALL_PRE void VMA_CALL_POST vmaFreeMemoryPages(

     VmaAllocator allocator,

     size_t allocationCount,

-    VmaAllocation* pAllocations)

+    const VmaAllocation* pAllocations)

 {

     if(allocationCount == 0)

     {

@@ -18098,7 +18098,7 @@
 

 VMA_CALL_PRE VkResult VMA_CALL_POST vmaDefragment(

     VmaAllocator allocator,

-    VmaAllocation* pAllocations,

+    const VmaAllocation* pAllocations,

     size_t allocationCount,

     VkBool32* pAllocationsChanged,

     const VmaDefragmentationInfo *pDefragmentationInfo,