servicemanager: TEST_MAPPING += libbinder tests

Import libbinder tests. Due to the global nature of the SM, these tests
frequently make use of the servicemanager.

Bug: 137203409
Test: TH
Change-Id: I40777d7e859ac7fdba686e12ef515406eace2c07
diff --git a/cmds/servicemanager/TEST_MAPPING b/cmds/servicemanager/TEST_MAPPING
index 3e47269..739740a 100644
--- a/cmds/servicemanager/TEST_MAPPING
+++ b/cmds/servicemanager/TEST_MAPPING
@@ -3,5 +3,10 @@
     {
       "name": "servicemanager_test"
     }
+  ],
+  "imports": [
+    {
+      "path": "frameworks/native/libs/binder"
+    }
   ]
 }