Adding back API so as not to be a breaking change

Author: RogPodge

Packages/com.unity.inputsystem/InputSystem/Plugins/XR/TrackedPoseDriver.cs

@@ -413,6 +413,13 @@ protected void Reset()
             m_TrackingStateInput = new InputActionProperty(new InputAction("Tracking State", expectedControlType: "Integer"));
         }
 
+        /// <summary>
+        /// This function is called when the script instance is being loaded.
+        /// </summary>
+        protected virtual void Awake()
+        {
+        }
+
         /// <summary>
         /// This function is called when the object becomes enabled and active.
         /// </summary>
@@ -437,6 +444,13 @@ protected void OnDisable()
             InputSystem.onDeviceChange -= OnDeviceChanged;
         }
 
+        /// <summary>
+        /// This function is called when the <see cref="MonoBehaviour"/> will be destroyed.
+        /// </summary>
+        protected virtual void OnDestroy()
+        {
+        }
+
         /// <summary>
         /// The callback method called after the Input System has completed an update and processed all pending events.
         /// </summary>