drm/i915/bxt: Set oscaledcompmethod to enable scale value

Bspec update tells that we have to enable oscaledcompmethod instead of
ouniqetrangenmethod for enabling scale value during swing programming.

v2: Adding back 'don't care' values to bxt_ddi_translations_dp and add
error message if ouniquetrangemethod was set (Imre)

Signed-off-by: Sonika Jindal <sonika.jindal@intel.com>
Reviewed-by: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com>(v1)
Reviewed-by: Imre Deak <imre.deak@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 56157eb..184b123 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -1395,7 +1395,8 @@
 #define BXT_PORT_TX_DW3_LN0(port)	_PORT3(port, _PORT_TX_DW3_LN0_A,  \
 						     _PORT_TX_DW3_LN0_B,  \
 						     _PORT_TX_DW3_LN0_C)
-#define   UNIQE_TRANGE_EN_METHOD	(1 << 27)
+#define   SCALE_DCOMP_METHOD		(1 << 26)
+#define   UNIQUE_TRANGE_EN_METHOD	(1 << 27)
 
 #define _PORT_TX_DW4_LN0_A		0x162510
 #define _PORT_TX_DW4_LN0_B		0x6C510