"import types" should never be necessary, it is implicit (if types.hal exists)

Change-Id: I63e6a2104415a5a71bf3eb93c646f9bf32f1b079
diff --git a/tests/foo/1.0/IFoo.hal b/tests/foo/1.0/IFoo.hal
index 8491cb0..a7df1aa 100644
--- a/tests/foo/1.0/IFoo.hal
+++ b/tests/foo/1.0/IFoo.hal
@@ -1,7 +1,6 @@
 package android.hardware.tests.foo@1.0;
 
 import IFooCallback;
-import types;
 
 interface IFoo {