make getting Chassis collection work with DPU BMCs (#323)

Fix incorrect Chassis.Controls link definition.

redfish/chassis.go

@@ -473,7 +473,7 @@ func (chassis *Chassis) UnmarshalJSON(b []byte) error {
 		temp
 		Assembly           common.Link
 		Certificates       common.Link
-		Controls           common.Links
+		Controls           common.Link
 		Drives             common.Link
 		EnvironmentMetrics common.Link
 		FabricAdapters     common.Link
@@ -504,6 +504,7 @@ func (chassis *Chassis) UnmarshalJSON(b []byte) error {
 	// Extract the links to other entities for later
 	chassis.assembly = t.Assembly.String()
 	chassis.certificates = t.Certificates.String()
+	chassis.controls = t.Controls.String()
 	chassis.drives = t.Drives.String()
 	chassis.environmentMetrics = t.EnvironmentMetrics.String()
 	chassis.fabricAdapters = t.FabricAdapters.String()

redfish/chassis_test.go

@@ -39,6 +39,9 @@ var chassisBody = `{
 		"Assembly": {
 			"@odata.id": "/redfish/v1/Chassis/Chassis-1/Assembly"
 		},
+		"Controls": {
+			"@odata.id": "/redfish/v1/Chassis/Chassis-1/Controls"
+		},
 		"Drives": {
 			"@odata.id": "/redfish/v1/Chassis/Chassis-1/Drives"
 		},
@@ -155,6 +158,10 @@ func TestChassis(t *testing.T) {
 		t.Errorf("Received invalid assembly reference: %s", result.assembly)
 	}
 
+	if result.controls != "/redfish/v1/Chassis/Chassis-1/Controls" {
+		t.Errorf("Received invalid controls reference: %s", result.controls)
+	}
+
 	if result.drives != "/redfish/v1/Chassis/Chassis-1/Drives" {
 		t.Errorf("Received invalid drive reference: %s", result.drives)
 	}