Add HAL for VR mode.

- Provide HAL for vendors to turn on VR-specific device performance
  settings when we enter VR mode in VrManagerService.

Bug: 22855417
Change-Id: I3dee920818eb0988452bf5c25d1a31f11fde7339
diff --git a/modules/Android.mk b/modules/Android.mk
index a77188d..3dc4ca6 100644
--- a/modules/Android.mk
+++ b/modules/Android.mk
@@ -1,4 +1,4 @@
 hardware_modules := gralloc hwcomposer audio nfc nfc-nci local_time \
 	power usbaudio audio_remote_submix camera usbcamera consumerir sensors vibrator \
-	tv_input fingerprint input vehicle hardware_properties
+	tv_input fingerprint input vehicle hardware_properties vr
 include $(call all-named-subdir-makefiles,$(hardware_modules))