Make CreateModule return the newly created module

Allow mutators to modify properties of the newly created module
by returning it.

Test: m checkbuild
Change-Id: I682caca86c0c8f7c3ae815a494d4c75962c8e2e8
diff --git a/android/hooks.go b/android/hooks.go
index 64ffd52..1e5ff21 100644
--- a/android/hooks.go
+++ b/android/hooks.go
@@ -30,7 +30,7 @@
 	BaseModuleContext
 	AppendProperties(...interface{})
 	PrependProperties(...interface{})
-	CreateModule(ModuleFactory, ...interface{})
+	CreateModule(ModuleFactory, ...interface{}) Module
 }
 
 // Arch hooks are run after the module has been split into architecture variants, and can be used