Revert "Revert "coredumpctl: in case of error free pattern after print""

In the case of the error set_consume will free the pointer 'pattern'
which is later used in log_error. Either we should stop priniting that
or use simple set_put and free pattern manually.

This reverts commit ece6b8fd5bbc1fee16f652e680e3033f2f3efc4a.