tests: Fix the make distcheck of libosmocore with the tests
diff --git a/tests/Makefile.am b/tests/Makefile.am
index aed0f13..4ab9773 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -36,6 +36,7 @@
 clean-local:
 	test ! -f '$(TESTSUITE)' || \
 		$(SHELL) '$(TESTSUITE)' --clean
+	$(RM) -f atconfig
      
 AUTOM4TE = $(SHELL) $(srcdir)/missing --run autom4te
 AUTOTEST = $(AUTOM4TE) --language=autotest