drm/i915: Pass dev_priv to rest of IS_FOO() macros for the old platforms

Unify our approach to things by passing around dev_priv instead of dev.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477946245-14134-22-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index afd3bab..7199f85 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -1530,7 +1530,7 @@ static void i9xx_update_wm(struct intel_crtc *unused_crtc)
 	int planea_wm, planeb_wm;
 	struct intel_crtc *crtc, *enabled = NULL;
 
-	if (IS_I945GM(dev))
+	if (IS_I945GM(dev_priv))
 		wm_info = &i945_wm_info;
 	else if (!IS_GEN2(dev_priv))
 		wm_info = &i915_wm_info;