undo last change as there's problems with the reports target, specifically the clover target calling clean to make sure the classes are instrumented

git-svn-id: https://pmd.svn.sourceforge.net/svnroot/pmd/trunk@6568 51baf565-9d33-0410-a72c-fc3788e3496d

pmd/build.xml

@@ -40,7 +40,6 @@
 		<delete file="${dir.lib}/pmd-src-${version}.jar" />
 		<delete file="${dir.lib}/pmd-test-${version}.jar" />
 		<delete dir="${dir.api}" />
-		<delete dir="${dir.reports}" />
 		<mkdir dir="${dir.build}" />
 	</target>