drm/i915: add haswell_set_pipeconf

It's a copy of ironlake_set_pipeconf with 2 differences:
  - There is no BPC field to set.
  - The interlaced mask is now 2 bits instead of 3.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index d1b58d0..fd9a319 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -2639,6 +2639,7 @@
 #define   PIPECONF_GAMMA		(1<<24)
 #define   PIPECONF_FORCE_BORDER	(1<<25)
 #define   PIPECONF_INTERLACE_MASK	(7 << 21)
+#define   PIPECONF_INTERLACE_MASK_HSW	(3 << 21)
 /* Note that pre-gen3 does not support interlaced display directly. Panel
  * fitting must be disabled on pre-ilk for interlaced. */
 #define   PIPECONF_PROGRESSIVE			(0 << 21)