make 'make clean' work on Solaris, per Gabor Greif comment

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@85958 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Makefile b/test/Makefile
index 75b8601..fdb9d8f 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -44,6 +44,6 @@
 	     $(PROJ_SRC_DIR)/lit.site.cfg.in > $@
 
 clean::
-	@ find -name Output | xargs rm -fr
+	@ find . -name Output | xargs rm -fr
 
 .PHONY: all report clean