drm/i915: Broaden FBC resolution limit to 4096*4096

Staring from HSW, the resolution limit of FBC has increased to
4096*4096

Issue: VIZ-2813
Change-Id: I842f64e3cf2c0d18d29ef1bcfef3b9bb1f1764ac
Signed-off-by: NDaisy Sun <daisy.sun@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_pm.c

@@ -530,7 +530,10 @@ void intel_update_fbc(struct drm_device *dev)
 		goto out_disable;
 	}
 
-	if (IS_G4X(dev) || INTEL_INFO(dev)->gen >= 5) {
+	if (INTEL_INFO(dev)->gen >= 8 || IS_HASWELL(dev)) {
+		max_width = 4096;
+		max_height = 4096;
+	} else if (IS_G4X(dev) || INTEL_INFO(dev)->gen >= 5) {
 		max_width = 4096;
 		max_height = 2048;
 	} else {