Added documentation for target (#26459)

* Added documentation for target

* Updated documentation message

docs/examples/en/controls/TrackballControls.html

@@ -171,6 +171,11 @@
 			Whether or not damping is disabled. Default is `false`.
 		</p>
 
+		<h3>[property:Vector3 target]</h3>
+		<p>
+			The focus point of the controls.
+		</p>
+
 		<h3>[property:Number zoomSpeed]</h3>
 		<p>
 			The zoom speed. Default is `1.2`.