Enable unused variable warnings and resolve

This commit enables the "unused variables" warning in clang.  Throughout
this, it did point out several issues that would've been functional
bugs, so I think it was worthwhile.  It also cleaned up several unused
variable from old constructs that no longer exist.

Tested:
Built with clang.  Code no longer emits warnings.

Downloaded bmcweb to system and pulled up the webui, observed webui
loads and logs in properly.

Change-Id: I51505f4222cc147d6f2b87b14d7e2ac4a74cafa8
Signed-off-by: Ed Tanous <ed@tanous.net>
diff --git a/include/image_upload.hpp b/include/image_upload.hpp
index a135af9..9d0a0ca 100644
--- a/include/image_upload.hpp
+++ b/include/image_upload.hpp
@@ -18,8 +18,7 @@
 
 static std::unique_ptr<sdbusplus::bus::match::match> fwUpdateMatcher;
 
-inline void uploadImageHandler(const crow::Request& req, crow::Response& res,
-                               const std::string& filename)
+inline void uploadImageHandler(const crow::Request& req, crow::Response& res)
 {
     // Only allow one FW update at a time
     if (fwUpdateMatcher != nullptr)
@@ -115,15 +114,13 @@
         .privileges({"ConfigureComponents", "ConfigureManager"})
         .methods(boost::beast::http::verb::post, boost::beast::http::verb::put)(
             [](const crow::Request& req, crow::Response& res,
-               const std::string& filename) {
-                uploadImageHandler(req, res, filename);
-            });
+               const std::string&) { uploadImageHandler(req, res); });
 
     BMCWEB_ROUTE(app, "/upload/image")
         .privileges({"ConfigureComponents", "ConfigureManager"})
         .methods(boost::beast::http::verb::post, boost::beast::http::verb::put)(
             [](const crow::Request& req, crow::Response& res) {
-                uploadImageHandler(req, res, "");
+                uploadImageHandler(req, res);
             });
 }
 } // namespace image_upload