REORG: include: move protocol.h to haproxy/protocol{,-t}.h

The protocol.h files are pretty low in the dependency and (sadly) used
by some files from common/. Almost nothing was changed except lifting a
few comments.
diff --git a/src/listener.c b/src/listener.c
index 04ce4e3..2f9c800 100644
--- a/src/listener.c
+++ b/src/listener.c
@@ -26,7 +26,7 @@
 #include <haproxy/time.h>
 
 #include <types/global.h>
-#include <types/protocol.h>
+#include <haproxy/protocol-t.h>
 
 #include <proto/acl.h>
 #include <proto/connection.h>
@@ -34,7 +34,7 @@
 #include <haproxy/freq_ctr.h>
 #include <proto/log.h>
 #include <proto/listener.h>
-#include <proto/protocol.h>
+#include <haproxy/protocol.h>
 #include <proto/proto_sockpair.h>
 #include <proto/sample.h>
 #include <proto/stream.h>