qemu-file: Use qemu_file_is_writable() on stdio_fclose() Use the existing function which checks if writev_buffer() or put_buffer() are set, instead of duplicating it. Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>