[PATCH 0/6] drm: Add mode object leases [v3]

[Keith Packard]

Here's a third version of my DRM mode object leases series. Since v2:

    * Add revocation. This allows leases to be effectively revoked by
      removing all of the objects they have access to. The lease itself
      hangs around as it's hanging off a file.
    
    * Allow non-master files to look at all DRM mode objects. This
      lets the Vulkan code provide information about the display
      environment before the lease is created.

    * Free the leases IDR when the master is destroyed. Just a bug fix.
    
    * _drm_lease_held should look at lessees, not lessor. Just a bug fix.
    
I've also rebased it to a more recent version of Dave's drm-next
branch.

With this and my CRTC-id based vblank series (posted separately), I'm
now running "real" applications on a leased output and can fully
support the following Vulkan extensions:

	EXT_direct_mode_display
	EXT_acquire_xlib_display
	EXT_display_surface_counter
	KEITHP_kms_display

-keith