Don't check for unused vars at configure time

The generate step should catch all of them.

Source/cmMakefile.cxx

@@ -831,8 +831,6 @@ void cmMakefile::ConfigureFinalPass()
     {
     l->second.FinishConfigure();
     }
-
-  this->GetCMakeInstance()->RunCheckForUnusedVariables("configure");
 }
 
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