We did this originally because these types are referred to in the bolts, and we
had no way of injecting the correct include lines into those. Now we do, so
there's less excuse for this.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We often want a pointer which will turn to NULL if the pointed-to thing is
freed. This is possible with tal objects, so create it.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>