THRIFT-3332 make dist fails on clean build

This closes #609
diff --git a/lib/cpp/test/Makefile.am b/lib/cpp/test/Makefile.am
index b19f791..44b94a7 100755
--- a/lib/cpp/test/Makefile.am
+++ b/lib/cpp/test/Makefile.am
@@ -368,5 +368,4 @@
 	qt \
 	CMakeLists.txt \
 	DebugProtoTest_extras.cpp \
-	tests.xml \
 	ThriftTest_extras.cpp