vulkan: update Vulkan headers to 1.1.72

Key changes from 1.1.68:
* Added VK_EXT_descriptor_indexing
* Added VK_EXT_vertex_attribute_divisor
* Added VK_AMD_buffer_marker
* Added VK_AMD_shader_core_properties
* Added VK_NV_shader_subgroup_partitioned

Test: run libvulkan and nulldrv codegen; no differences in generated
      code, as expected
Test: build system image
Change-Id: Ic204e40bef6cabb1047e5ac38347424c3955c385