MINOR: ssl: add defines LISTEN_DEFAULT_CIPHERS and CONNECT_DEFAULT_CIPHERS.

These ones are used to set the default ciphers suite on "bind" lines and
"server" lines respectively, instead of using OpenSSL's defaults. These
are probably mainly useful for distro packagers.
diff --git a/include/common/defaults.h b/include/common/defaults.h
index b49044e..3a67d33 100644
--- a/include/common/defaults.h
+++ b/include/common/defaults.h
@@ -188,4 +188,14 @@
 #define HCHK_DESC_LEN	128
 #endif
 
+/* ciphers used as defaults on connect */
+#ifndef CONNECT_DEFAULT_CIPHERS
+#define CONNECT_DEFAULT_CIPHERS NULL
+#endif
+
+/* ciphers used as defaults on listeners */
+#ifndef LISTEN_DEFAULT_CIPHERS
+#define LISTEN_DEFAULT_CIPHERS NULL
+#endif
+
 #endif /* _COMMON_DEFAULTS_H */