drm/i915: Make IS_VALLEYVIEW only take dev_priv

Saves 944 bytes of .rodata strings and 128 bytes of .text.

v2: Add parantheses around dev_priv. (Ville Syrjala)

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: David Weinehall <david.weinehall@linux.intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Jani Nikula <jani.nikula@linux.intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index d36b507..8967a8d 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -7771,7 +7771,7 @@
 	} else if (IS_CHERRYVIEW(dev_priv)) {
 		vlv_setup_wm_latency(dev);
 		dev_priv->display.update_wm = vlv_update_wm;
-	} else if (IS_VALLEYVIEW(dev)) {
+	} else if (IS_VALLEYVIEW(dev_priv)) {
 		vlv_setup_wm_latency(dev);
 		dev_priv->display.update_wm = vlv_update_wm;
 	} else if (IS_PINEVIEW(dev)) {