Check stack depth in new recursive functions

Check stack depth in new recursive functions

Commit b0e96f311985 introduced a bunch of recursive functions, but
failed to make them check for stack depth.  This can cause the backend
to crash when operating on inheritance hierarchies several thousands
deep.  Protect the code by adding the missing stack depth checks.

Reported-by: Alexander Lakhin <[email protected]>
Discussion: https://postgr.es/m/b2ac2392-9727-5f76-e890-721ac80c1615@gmail.com