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/types/listener.h b/include/types/listener.h
index 4b71ddb..997a597 100644
--- a/include/types/listener.h
+++ b/include/types/listener.h
@@ -27,7 +27,6 @@
 
 #ifdef USE_OPENSSL
 #include <common/openssl-compat.h>
-#include <types/ssl_sock.h>
 #endif
 
 #include <common/config.h>
@@ -112,6 +111,12 @@
 #define BC_SSL_O_PREF_CLIE_CIPH 0x0200  /* prefer client ciphers */
 #endif
 
+struct tls_version_filter {
+	uint16_t flags;     /* ssl options */
+	uint8_t  min;      /* min TLS version */
+	uint8_t  max;      /* max TLS version */
+};
+
 /* ssl "bind" settings */
 struct ssl_bind_conf {
 #ifdef USE_OPENSSL