(libgcc.a): Allow chmod of tmpcopy directory to fail since it can be

empty.

From-SVN: r6286

gcc/Makefile.in

@@ -751,7 +751,7 @@ libgcc.a: $(LIBGCC1) $(LIBGCC2)
 # unwritable table of contents file, and then print an error message when
 # the second ar command tries to overwrite this file.  To avoid the error
 # message from ar, we make sure all files are writable.
-	(cd tmpcopy; chmod +w * > /dev/null 2>&1)
+	-(cd tmpcopy; chmod +w * > /dev/null 2>&1)
 	(cd tmpcopy; $(AR) x ../$(LIBGCC2))
 	(cd tmpcopy; $(AR) $(AR_FLAGS) ../tmplibgcc.a *.o)
 	rm -rf tmpcopy