Power HAL target-side test

Test: make vts; vts-tradefed run -m HalPowerHidlTargetTest
Bug: 32022775
Change-Id: Id6a14ceb24e6a13e49a236357198686b4348809a
Signed-off-by: Connor O'Brien <connoro@google.com>
diff --git a/power/Android.bp b/power/Android.bp
index ba90f2c..ed19a37 100644
--- a/power/Android.bp
+++ b/power/Android.bp
@@ -2,4 +2,5 @@
 subdirs = [
     "1.0",
     "1.0/default",
+    "1.0/vts/functional",
 ]