MAJOR: proxy/htx: Handle mux upgrades from TCP to HTTP in HTX mode

It is now possible to upgrade TCP streams to HTX when an HTTP backend is set for
a TCP frontend (both with the HTX enabled). So concretely, in such case, an
upgrade is performed from the mux pt to the mux h1. The current CS and the
channel's buffer are used to initialize the mux h1.
1 file changed