Fix link in plugin docs

Change-Id: I4f7ce3afaca111203126681b76f3f493b0a44faf
diff --git a/packages/SystemUI/docs/plugins.md b/packages/SystemUI/docs/plugins.md
index ed91f3d..6892005 100644
--- a/packages/SystemUI/docs/plugins.md
+++ b/packages/SystemUI/docs/plugins.md
@@ -73,7 +73,7 @@
 1. They must be signed with the platform cert
 2. They must include SystemUIPluginLib in LOCAL_JAVA_LIBRARIES (NOT LOCAL_STATIC_JAVA_LIBRARIES)
 
-Basically just copy the [example file](/packages/SystemUI/plugin/ExamplePlugin/Android.mk).
+Basically just copy the [example blueprint file](/packages/SystemUI/plugin/ExamplePlugin/Android.bp).
 
 To declare a plugin, you add a service to your manifest.  Add an intent filter to match the action for the plugin, and set the name to point at the class that implements the plugin interface.