curl: expanded the -XHEAD warning text

... to also mention the specific options used.

src/tool_helpers.c

@@ -110,7 +110,7 @@ void customrequest_helper(struct OperationConfig *config, HttpReq req,
   }
   else if(curl_strequal(method, "head")) {
     warnf(config->global,
-          "Setting custom HTTP method to HEAD may not work the way you "
-          "want.\n");
+          "Setting custom HTTP method to HEAD with -X/--request may not work "
+          "the way you want. Consider using -I/--head instead.\n");
   }
 }