Remove deprecated constant TL1

Change-Id: I6ff4a515fa9d5e5a241fc6ec32c17878b57cec05
diff --git a/providers/tl1/device/src/main/java/org/onosproject/provider/tl1/device/impl/Tl1DeviceProvider.java b/providers/tl1/device/src/main/java/org/onosproject/provider/tl1/device/impl/Tl1DeviceProvider.java
index 04c3120..b9a6237 100644
--- a/providers/tl1/device/src/main/java/org/onosproject/provider/tl1/device/impl/Tl1DeviceProvider.java
+++ b/providers/tl1/device/src/main/java/org/onosproject/provider/tl1/device/impl/Tl1DeviceProvider.java
@@ -71,11 +71,6 @@
 @Component(immediate = true)
 public class Tl1DeviceProvider extends AbstractProvider implements DeviceProvider {
     private static final String APP_NAME = "org.onosproject.tl1";
-    /**
-     * @deprecated in 1.11.0. Use {@link Tl1DeviceConfig#TL1} instead
-     */
-    @Deprecated
-    protected static final String TL1 = Tl1DeviceConfig.TL1;
     private static final String PROVIDER = "org.onosproject.provider.tl1.device";
     private static final String UNKNOWN = "unknown";
     private static final int REACHABILITY_TIMEOUT = 2000;      // in milliseconds