panfrost: Create scanout kmsro buffer when shared
What does this MR do and why?
Create a scanout-ready resource if the buffer might ever have resource_get_handle(WINSYS_HANDLE_TYPE_KMS) called on it. create_with_modifiers() doesn't give us usage flags, so we have to assume that all calls with PIPE_BIND_SHARED are scanout-possible.
This patch has been lying in my v10 branch for too long. I think it's time to upstream it, or find an alternative solution...
/cc @kusma