Fix unused variables

In almost all cases these can be removed. The only exception is in
ShaderViewer.cpp, where regIdx should have been used.

qrenderdoc/Code/pyrenderdoc/PythonContext.cpp

@@ -410,10 +410,6 @@ PythonContext::PythonContext(QObject *parent) : QObject(parent)
   // clone our own local context
   context_namespace = PyDict_Copy(main_dict);
 
-  QString typeStr;
-  QString valueStr;
-  QList<QString> frames;
-
   // for compatibility with earlier versions of python that took a char * instead of const char *
   char noparams[1] = "";
 
@@ -873,4 +869,4 @@ extern "C" void SetThreadBlocking(PyObject *global_handle, bool block)
   OutputRedirector *redirector = (OutputRedirector *)global_handle;
   if(redirector && redirector->context)
     return redirector->context->setThreadBlocking(block);
-}
+}