drm/i915: Use INTEL_GEN everywhere

Coccinelle patch:

 @@
 identifier p;
 @@
 -INTEL_INFO(p)->gen
 +INTEL_GEN(p)

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180208130606.15556-12-tvrtko.ursulin@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20180209215847.6660-1-chris@chris-wilson.co.uk
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index ef80499..4677ac0 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -189,7 +189,7 @@ static void intel_lvds_pps_get_hw_state(struct drm_i915_private *dev_priv,
 	/* Convert from 100ms to 100us units */
 	pps->t4 = val * 1000;
 
-	if (INTEL_INFO(dev_priv)->gen <= 4 &&
+	if (INTEL_GEN(dev_priv) <= 4 &&
 	    pps->t1_t2 == 0 && pps->t5 == 0 && pps->t3 == 0 && pps->tx == 0) {
 		DRM_DEBUG_KMS("Panel power timings uninitialized, "
 			      "setting defaults\n");