REORG: ssl: move ssl_sock_ctx and fix cross-dependencies issues

In order to move all SSL sample fetches in another file, moving the
ssl_sock_ctx definition in a .h file is required.

Unfortunately it became a cross dependencies hell to solve, because of
the struct wait_event field, so <types/connection.h> is needed which
created other problems.
diff --git a/include/proto/ssl_sock.h b/include/proto/ssl_sock.h
index a01e29e..32b7a33 100644
--- a/include/proto/ssl_sock.h
+++ b/include/proto/ssl_sock.h
@@ -28,6 +28,7 @@
 #include <types/connection.h>
 #include <types/listener.h>
 #include <types/proxy.h>
+#include <types/ssl_sock.h>
 #include <types/stream_interface.h>
 
 #include <proto/connection.h>