This patch fixes all the leftovers from the include cleanup campaign. There were not that many (~400 entries in ~150 files) but it was definitely worth doing it as it revealed a few duplicates.
The files were moved with no change. The callers were cleaned up a bit and a few of them had channel.h removed since not needed.
There's no type file for this trivial one. The unneeded dependency on htx.h was dropped.
