libvulkan: Check whether gralloc can do protected content

Certain devices don't support protected allocations at the gralloc level; having libvulkan claim they are supported leads to problems later when an app attempts to create a protected swapchain

Bug: b/416472139
Flag: EXEMPT bugfix
Test: atest CtsDeqpTestCases -- --module-arg CtsDeqpTestCases:include-filter:dEQP-VK.protected_memory.interaction.wsi.android.swapchain.render.basic

Change-Id: I952a205bb98694b746255132dc98988be98d5f19