header: Update to 1.0.54 Vulkan release

Update the headers and xml file with the latest spec changes for
Vulkan 1.0.54.  Also, make corresponding loader and layer changes
to support the new extensions.

Change-Id: I11273c5e3e828743f904e4f0b4b2f2c3a7804df0
diff --git a/scripts/unique_objects_generator.py b/scripts/unique_objects_generator.py
index 7effe03..3af26fb 100644
--- a/scripts/unique_objects_generator.py
+++ b/scripts/unique_objects_generator.py
@@ -147,6 +147,9 @@
             'vkCmdPushDescriptorSetWithTemplateKHR',
             'vkDebugMarkerSetObjectTagEXT',
             'vkDebugMarkerSetObjectNameEXT',
+            'vkGetPhysicalDeviceDisplayProperties2KHR',
+            'vkGetPhysicalDeviceDisplayPlaneProperties2KHR',
+            'vkGetDisplayModeProperties2KHR',
             ]
         # Commands shadowed by interface functions and are not implemented
         self.interface_functions = [