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/CaptureContext.cpp

@@ -86,8 +86,6 @@ CaptureContext::CaptureContext(QString paramFilename, QString remoteHost, uint32
 
   if(!paramFilename.isEmpty())
   {
-    QFileInfo fi(paramFilename);
-
     m_MainWindow->LoadFromFilename(paramFilename, temp);
     if(temp)
       m_MainWindow->takeCaptureOwnership();

qrenderdoc/Code/Interface/CommonPipelineState.cpp

@@ -461,8 +461,6 @@ ResourceId CommonPipelineState::GetShader(ShaderStage stage)
 
 QString CommonPipelineState::GetShaderName(ShaderStage stage)
 {
-  QString ret;
-
   if(IsCaptureLoaded())
   {
     if(IsCaptureD3D11())

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);
-}
+}