Merge changes I3fe46024,I5925dbc4,Iefb9f82d,I39643a75,I16f9e5fd, ...

* changes:
  vulkan: Allow AHB extension to get to the driver
  libvulkan: correctly expose VK_KHR_shared_presentable_image
  Enable VK_KHR_swapchain for instances.
  vkGetDeviceQueue2: add a NULL check
  stubhal: add EnumeratePhysicalDeviceGroups
  libvulkan: Add VK_ANDROID_external_memory_android_hardware_buffer
  vulkan: Declare VK_ANDROID_external_memory_android_hardware_buffer
  vulkan: update Vulkan headers to 1.1.68
  Add VK1.1 entries to NDK libvulkan and fix a bug
  Properly implement stubhal's vkGetInstanceProcAddr()
  Vulkan1.1: CreateInstance downgrades apiVersion for 1.0 ICDs
  Additional changes to Vulkan 1.1 API updates
  Vulkan api update to 1.1