drm/i915/dg2: add DG2+ TRANS_DDI_FUNC_CTL DP 2.0 128b/132b mode

Unfortunately, the DP 2.0 128b/132b DDI mode selection in the register
conflicts with FDI. Since we have to deal with both meanings in the same
code, for different platforms, clarify the macro name so we don't
forget.

Bspec: 50493
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/260e4da302d47ae50122eb8d517be6ac3ccb15f2.1631191763.git.jani.nikula@intel.com
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 67351ed..61d29068 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -10173,7 +10173,7 @@ enum skl_power_gate {
 #define  TRANS_DDI_MODE_SELECT_DVI	(1 << 24)
 #define  TRANS_DDI_MODE_SELECT_DP_SST	(2 << 24)
 #define  TRANS_DDI_MODE_SELECT_DP_MST	(3 << 24)
-#define  TRANS_DDI_MODE_SELECT_FDI	(4 << 24)
+#define  TRANS_DDI_MODE_SELECT_FDI_OR_128B132B	(4 << 24)
 #define  TRANS_DDI_BPC_MASK		(7 << 20)
 #define  TRANS_DDI_BPC_8		(0 << 20)
 #define  TRANS_DDI_BPC_10		(1 << 20)