anv: Fix feature pipelineProtectedAccess
This looks like a simple bug to me. I found it by code inspection and have not tested it. If this MR is wrong, please let me know.
We enable VK_EXT_pipeline_protected_access
only if anv_physical_device::has_protected_contexts
. Therefore we should do the same
for vk_features::pipelineProtectedAccess
.