st-hal-ar: add TARGET_USES_QCOM_AUDIO_AR guard

Change-Id: Ic2e3073fefe3643df794be40a4991ed465393c2d
diff --git a/Android.mk b/Android.mk
index 29efff1..07904cb 100644
--- a/Android.mk
+++ b/Android.mk
@@ -1,5 +1,6 @@
 ifneq ($(AUDIO_USE_STUB_HAL), true)
 ifeq ($(TARGET_USES_QCOM_MM_AUDIO),true)
+ifeq ($(TARGET_USES_QCOM_AUDIO_AR),true)
 
 LOCAL_PATH := $(call my-dir)
 
@@ -55,5 +56,6 @@
 endif
 
 include $(BUILD_SHARED_LIBRARY)
+endif #TARGET_USES_QCOM_AUDIO_AR
 endif #TARGET_USES_QCOM_MM_AUDIO
 endif #AUDIO_USE_STUB_HAL