layers: Fix enum cross reference to handle missing
layers: Fix enum cross reference to handle missing

Modify enum cross reference table creation to handle missing items from
VK_DEBUG_REPORT_OBJECT_TYPE_ list, as it is no longer being updated.

Change-Id: I112a08f82249c446757495309699c80fe7094635

KhronosGroup/Vulkan-Tools,KhronosGroup/Vulkan-Tools,KhronosGroup/Vulkan-Tools,KhronosGroup/Vulkan-Tools