Don't build libbt-hidlclient for OSS builds

* Requires proprietary headers

Change-Id: I79ab50d31f5d67deb1cfb79cd410fe993017cbe8
diff --git a/tools/hidl_client/Android.mk b/tools/hidl_client/Android.mk
index 8dab06a..4bf7bbe 100644
--- a/tools/hidl_client/Android.mk
+++ b/tools/hidl_client/Android.mk
@@ -1,7 +1,6 @@
 LOCAL_PATH:= $(call my-dir)
 
-
-
+ifneq ($(QCPATH),)
 include $(CLEAR_VARS)
 
 LOCAL_SRC_FILES:=     \
@@ -29,3 +28,4 @@
 LOCAL_MODULE_TAGS := optional
 
 include $(BUILD_SHARED_LIBRARY)
+endif