add notion of topdir to Makefile.lite build system
diff --git a/test/Makefile.lite b/test/Makefile.lite
index 0e53fa1..58ebc62 100644
--- a/test/Makefile.lite
+++ b/test/Makefile.lite
@@ -18,6 +18,9 @@
 #
 # GNU makefile
 #
+
+topdir = ..
+
 all: clean
 	FLAC__EXHAUSTIVE_TESTS=yes ./test_libFLAC.sh
 	FLAC__EXHAUSTIVE_TESTS=yes ./test_libFLAC++.sh