Switch to use rs_version.mk for consistency.

Change-Id: Ia19bb2f56653b10741d8b508c3dc3f93ce1c1495
diff --git a/libbcc-device-build.mk b/libbcc-device-build.mk
index 639a0d6..5324e15 100644
--- a/libbcc-device-build.mk
+++ b/libbcc-device-build.mk
@@ -21,6 +21,7 @@
   -Wno-unused-parameter \
   -Werror \
   -DTARGET_BUILD \
+  $(RS_VERSION_DEFINE) \
   $(LOCAL_CFLAGS)
 
 ifeq ($(TARGET_BUILD_VARIANT),eng)