build: goldfish: add emulator Power HAL

Change-Id: Id6de532d56dabcb8709bb3e331780c8b7f508973
Signed-off-by: Todd Poynor <toddpoynor@google.com>
diff --git a/target/board/generic/device.mk b/target/board/generic/device.mk
index 4edcc19..ee8e273 100644
--- a/target/board/generic/device.mk
+++ b/target/board/generic/device.mk
@@ -28,4 +28,5 @@
     development/tools/emulator/system/camera/media_profiles.xml:system/etc/media_profiles.xml \
 
 PRODUCT_PACKAGES := \
-    audio.primary.goldfish
+    audio.primary.goldfish \
+    power.goldfish