dzn: Add a dummy GetImageSparseMemoryRequirements2()

We don't support sparse memory yet, but this function needs to be
present.

Reviewed-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Reviewed-by: Jesse Natalie <jenatali@microsoft.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/16926>

src/microsoft/vulkan/dzn_device.c

@@ -2813,3 +2813,12 @@ dzn_GetDeviceGroupPeerMemoryFeatures(VkDevice device,
 {
    *pPeerMemoryFeatures = 0;
 }
+
+VKAPI_ATTR void VKAPI_CALL
+dzn_GetImageSparseMemoryRequirements2(VkDevice device,
+                                      const VkImageSparseMemoryRequirementsInfo2* pInfo,
+                                      uint32_t *pSparseMemoryRequirementCount,
+                                      VkSparseImageMemoryRequirements2 *pSparseMemoryRequirements)
+{
+   *pSparseMemoryRequirementCount = 0;
+}