libctf: prohibit nameless ints, floats, typedefs and forwards

libctf: prohibit nameless ints, floats, typedefs and forwards

Now that "anonymous typedef nodes" have been extirpated, we can mandate
that things that have names in C must have names in CTF too.  (Unlike
the no-forwards embarrassment, the deduplicator does nothing special
with names: types that have names in C will have the same name in CTF.
So we can assume that the CTF rules and the C rules are the same.)

include/ChangeLog
2021-01-27  Nick Alcock  <nick.alcock@oracle.com>

	* ctf-api.h (ECTF_NONAME): New.
	(ECTF_NERR): Adjust.

libctf/ChangeLog
2021-01-27  Nick Alcock  <nick.alcock@oracle.com>

	* ctf-create.c (ctf_add_encoded): Add check for non-empty name.
	(ctf_add_forward): Likewise.
	(ctf_add_typedef): Likewise.