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/src/webserver_main.cpp b/src/webserver_main.cpp
index b626f5b..922ac47 100644
--- a/src/webserver_main.cpp
+++ b/src/webserver_main.cpp
@@ -60,7 +60,7 @@
     }
 }
 
-int main(int argc, char** argv)
+int main(int /*argc*/, char** /*argv*/)
 {
     crow::logger::setLogLevel(crow::LogLevel::Debug);