drm/i915/adlp: Fix TypeC PHY-ready status readout

The TCSS_DDI_STATUS register is indexed by tc_port not by the FIA port
index, fix this up. This only caused an issue on TC#3/4 ports in legacy
mode, as in all other cases the two indices either match (on TC#1/2) or
the TCSS_DDI_STATUS_READY flag is set regardless of something being
connected or not (on TC#1/2/3/4 in dp-alt and tbt-alt modes).
Reported-and-tested-by: Chia-Lin Kao (AceLan) <acelan.kao@canonical.com>
Fixes: 55ce306c ("drm/i915/adl_p: Implement TC sequences")
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/4698
Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: <stable@vger.kernel.org> # v5.14+
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220126104356.2022975-1-imre.deak@intel.com

drivers/gpu/drm/i915/display/intel_tc.c

@@ -346,10 +346,11 @@ static bool icl_tc_phy_status_complete(struct intel_digital_port *dig_port)
 static bool adl_tc_phy_status_complete(struct intel_digital_port *dig_port)
 {
 	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
+	enum tc_port tc_port = intel_port_to_tc(i915, dig_port->base.port);
 	struct intel_uncore *uncore = &i915->uncore;
 	u32 val;
 
-	val = intel_uncore_read(uncore, TCSS_DDI_STATUS(dig_port->tc_phy_fia_idx));
+	val = intel_uncore_read(uncore, TCSS_DDI_STATUS(tc_port));
 	if (val == 0xffffffff) {
 		drm_dbg_kms(&i915->drm,
 			    "Port %s: PHY in TCCOLD, assuming not complete\n",