drm/i915: move psr_setup_done to psr struct

"Because our driver assumes only one panel is PSR capable, and we
already have other PSR information on dev_priv instead of intel_dp. If
we ever support multiple PSR panels, we'll have to move struct
i915_psr to intel_dp anyway." (by Paulo)

v2: Avoid more than one setup. Removing initialization
    and trusting allocation. (By Paulo Zanoni).
v3: rebase.
v4: Adding comment.

Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 49414d3..ef7ab0a 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -638,6 +638,7 @@
 struct i915_psr {
 	bool sink_support;
 	bool source_ok;
+	bool setup_done;
 };
 
 enum intel_pch {