message: Make OSX_ICONFILE Apple specific
  Wrap it with if (APPLE) and APPEND to the config file
diff: @@ -190,12 +190,12 @@ file(WRITE
  "LIBS+=${PYTHON_LINK}\n"
  "\n"
  "RENDERDOC_VERSION=${RENDERDOC_VERSION}\n"
  - "\n"
  - "OSX_ICONFILE=${CMAKE_CURRENT_BINARY_DIR}/RenderDoc.icns\n")
  + "\n")
  if(APPLE)
  file(APPEND
  ${CMAKE_BINARY_DIR}/qrenderdoc/qrenderdoc_cmake.pri
  + "OSX_ICONFILE=${CMAKE_CURRENT_BINARY_DIR}/RenderDoc.icns\n"
  "QMAKE_MACOSX_DEPLOYMENT_TARGET=${CMAKE_OSX_DEPLOYMENT_TARGET}\n")
  endif()
  