drm/i915: use PIPECONF_INTERLACE_MASK_HSW on lpt_enable_pch_transcoder

... instead of PIPECONF_INTERLACE_MASK.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
[danvet: applied the change by hand due to patch reorder.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 7bab7ad..787e62a4 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -1732,7 +1732,8 @@
 	val = TRANS_ENABLE;
 	pipeconf_val = I915_READ(PIPECONF(cpu_transcoder));
 
-	if ((pipeconf_val & PIPECONF_INTERLACE_MASK) == PIPECONF_INTERLACED_ILK)
+	if ((pipeconf_val & PIPECONF_INTERLACE_MASK_HSW) ==
+	    PIPECONF_INTERLACED_ILK)
 		val |= TRANS_INTERLACED;
 	else
 		val |= TRANS_PROGRESSIVE;