libvulkan: fix support for promoted VK_KHR_external_* extensions

This change intercepts below entry points:
vkGetPhysicalDeviceExternalBufferProperties
vkGetPhysicalDeviceExternalSemaphoreProperties
vkGetPhysicalDeviceExternalFenceProperties

Bug: 160276146
Test: adb shell cmd gpu vkjson
Test: dEQP-VK.api.external.*
Change-Id: I08e5647fd7ea48c2a0b2e28ef688dee44f85684c
5 files changed