Since the legacy HTTP mode was removed, the stream is always released at the end
of each HTTP transaction and a new is created to handle the next request for
keep-alive connections. So the HTTP transaction is no longer reset and the
function http_reset_txn() can be removed.
The old module proto_http does not exist anymore. All code dedicated to the HTTP
analysis is now grouped in the file proto_htx.c. So, to finish the polishing
after removing the legacy HTTP code, proto_htx.{c,h} files have been moved in
http_ana.{c,h} files.
In addition, all HTX analyzers and related functions prefixed with "htx_" have
been renamed to start with "http_" instead.