drm/amd/pm: change return value in aldebaran_get_power_limit()

v1:
1. change return value to avoid smu driver probe fails when FEATURE_PPT is
not enabled.
2. if FEATURE_PPT is not enabled, set power limit value to 0.

v2:
instead dev_err with dev_warn
Signed-off-by: Kevin Wang <kevin1.wang@amd.com>
Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/pm/swsmu/smu13/aldebaran_ppt.c

@@ -1193,8 +1193,19 @@ static int aldebaran_get_power_limit(struct smu_context *smu,
 	uint32_t power_limit = 0;
 	int ret;
 
-	if (!smu_cmn_feature_is_enabled(smu, SMU_FEATURE_PPT_BIT))
-		return -EINVAL;
+	if (!smu_cmn_feature_is_enabled(smu, SMU_FEATURE_PPT_BIT)) {
+		if (current_power_limit)
+			*current_power_limit = 0;
+		if (default_power_limit)
+			*default_power_limit = 0;
+		if (max_power_limit)
+			*max_power_limit = 0;
+
+		dev_warn(smu->adev->dev,
+			"PPT feature is not enabled, power values can't be fetched.");
+
+		return 0;
+	}
 
 	/* Valid power data is available only from primary die.
 	 * For secondary die show the value as 0.