Add IKVM.PdbWriter.dll to clean list.

ikvm.build

@@ -39,6 +39,7 @@
                 <include name="bin/IKVM.OpenJDK.Text.dll" />
                 <include name="bin/IKVM.OpenJDK.Util.dll" />
                 <include name="bin/IKVM.OpenJDK.XML.dll" />
+                <include name="bin/IKVM.PdbWriter.dll" />
                 <include name="bin/ikvm-native.dll" />
                 <include name="bin/libikvm-native.so" />
                 <include name="bin/ikvm.exe" />