This patch updates include/ctf.h to match the current libctf version in
binutils' include/.  I recently attempted to build a uber tree (following
some notes that are so old they used CVS) and noticed that binutils won't
build with gcc's top-level include, due to CTF_F_IDXSORTED not being
defined in ctf.h.

2023-04-28  Roger Sayle  <roger@nextmovesoftware.com>

include/ChangeLog
	* ctf.h: Import latest version from binutils/libctf.