Fire the onDel() callbacks for node deletion.

async def wasDeleted(self, node):
        '''
        Fire the onDel() callbacks for node deletion.
        '''
        for func in self.ondels:
            try:
                retn = func(node)
                if s_coro.iscoro(retn):
                    await retn
            except asyncio.CancelledError:
                raise
            except Exception:
                logger.exception('error on ondel for %s' % (self.name,))

        await node.snap.core.triggers.runNodeDel(node)