Remove GetDefaultPageSize

Duplicate. We already have the API for this: `Platform::GetCPUInfo().PageSize`.

Source/Engine/Platform/Base/PlatformBase.h

@@ -316,11 +316,6 @@ public:
     /// <param name="ptr">A pointer to the memory block to deallocate.</param>
     static void Free(void* ptr) = delete;
 
-    /// <summary>
-    /// Returns the OS's default page size that can be used with AllocatePages.
-    /// </summary>
-    static uint64 GetDefaultPageSize() = delete;
-
     /// <summary>
     /// Allocates pages memory block.
     /// </summary>