Add MicrodroidHostTestCases to TEST_MAPPING

Test: presubmit
Change-Id: I9cd6f575f0d7c9764103d09a44a128290bbaf973
diff --git a/TEST_MAPPING b/TEST_MAPPING
index db12ffe..83021d0 100644
--- a/TEST_MAPPING
+++ b/TEST_MAPPING
@@ -14,6 +14,9 @@
                 }
 
             ]
+        },
+        {
+            "name": "MicrodroidHostTestCases"
         }
     ]
 }