REORG: ssl: move utility functions to src/ssl_utils.c

These functions are mainly used to extract information from
certificates.
diff --git a/src/ssl_ckch.c b/src/ssl_ckch.c
index 484997d..c593649 100644
--- a/src/ssl_ckch.c
+++ b/src/ssl_ckch.c
@@ -35,6 +35,7 @@
 #include <proto/channel.h>
 #include <proto/ssl_ckch.h>
 #include <proto/ssl_sock.h>
+#include <proto/ssl_utils.h>
 #include <proto/stream_interface.h>
 
 /* Uncommitted CKCH transaction */