nghttpx: Update usage

src/shrpx.cc

@@ -467,9 +467,11 @@ void print_help(std::ostream& out)
   print_usage(out);
   out << "Positional arguments:\n"
       << "    <PRIVATE_KEY>      Set path to server's private key. Required\n"
-      << "                       unless either -p or --client is specified.\n"
+      << "                       unless -p, --client or --frontend-no-tls\n"
+      << "                       are given.\n"
       << "    <CERT>             Set path to server's certificate. Required\n"
-      << "                       unless either -p or --client is specified.\n"
+      << "                       unless -p, --client or --frontend-no-tls\n"
+      << "                       are given.\n"
       << "\n"
       << "OPTIONS:\n"
       << "\n"
@@ -569,10 +571,12 @@ void print_help(std::ostream& out)
       << "    --honor-cipher-order\n"
       << "                       Honor server cipher order, giving the\n"
       << "                       ability to mitigate BEAST attacks.\n"
-      << "    -k, --insecure     When used with -p or --client, don't verify\n"
-      << "                       backend server's certificate.\n"
-      << "    --cacert=<PATH>    When used with -p or --client, set path to\n"
-      << "                       trusted CA certificate file.\n"
+      << "    -k, --insecure     Don't verify backend server's certificate\n"
+      << "                       if -p, --client or --http2-bridge are given\n"
+      << "                       and --backend-no-tls is not given\n"
+      << "    --cacert=<PATH>    Set path to trusted CA certificate file\n"
+      << "                       if -p, --client or --http2-bridge are given\n"
+      << "                       and --backend-no-tls is not given\n"
       << "                       The file must be in PEM format. It can\n"
       << "                       contain multiple certificates. If the\n"
       << "                       linked OpenSSL is configured to load system\n"