drm/i915: add definition of LPT FDI port width registers

v2: change bits names to align better with other bits style
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_reg.h

@@ -3657,6 +3657,9 @@
 #define  FDI_LINK_TRAIN_PATTERN_IDLE_CPT	(2<<8)
 #define  FDI_LINK_TRAIN_NORMAL_CPT		(3<<8)
 #define  FDI_LINK_TRAIN_PATTERN_MASK_CPT	(3<<8)
+/* LPT */
+#define  FDI_PORT_WIDTH_2X_LPT			(1<<19)
+#define  FDI_PORT_WIDTH_1X_LPT			(0<<19)
 
 #define _FDI_RXA_MISC            0xf0010
 #define _FDI_RXB_MISC            0xf1010