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

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.
diff --git a/src/ssl_crtlist.c b/src/ssl_crtlist.c
index 118a6d1..3890ca8 100644
--- a/src/ssl_crtlist.c
+++ b/src/ssl_crtlist.c
@@ -15,6 +15,7 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 
+#include <haproxy/channel.h>
 #include <haproxy/cli.h>
 #include <haproxy/errors.h>
 #include <haproxy/ssl_ckch.h>
@@ -27,8 +28,6 @@
 #include <import/ebpttree.h>
 #include <import/ebsttree.h>
 
-#include <proto/channel.h>
-
 /* release ssl bind conf */
 void ssl_sock_free_ssl_conf(struct ssl_bind_conf *conf)
 {