Document "none" value for ca_path/ca_file in ssl_client2/ssl_server2
diff --git a/programs/ssl/ssl_server2.c b/programs/ssl/ssl_server2.c
index f5d370b..a4c5fab 100644
--- a/programs/ssl/ssl_server2.c
+++ b/programs/ssl/ssl_server2.c
@@ -188,8 +188,10 @@
 #define USAGE_IO \
     "    ca_file=%%s          The single file containing the top-level CA(s) you fully trust\n" \
     "                        default: \"\" (pre-loaded)\n" \
+    "                        use \"none\" to skip loading any top-level CAs.\n" \
     "    ca_path=%%s          The path containing the top-level CA(s) you fully trust\n" \
     "                        default: \"\" (pre-loaded) (overrides ca_file)\n" \
+    "                        use \"none\" to skip loading any top-level CAs.\n" \
     "    crt_file=%%s         Your own cert and chain (in bottom to top order, top may be omitted)\n" \
     "                        default: see note after key_file2\n" \
     "    key_file=%%s         default: see note after key_file2\n" \