message: Update the podspec template variable name
diff: @@ -4,7 +4,7 @@ Pod::Spec.new do |s|
  s.authors = 'Google Inc.'
  s.license = { :type => 'Apache' }
  s.homepage = 'https://github.com/tensorflow/tensorflow'
  - s.source = { :http => "${TFL_DOWNLOAD_URL_PREFIX}/TensorFlowLiteC-#{s.version}.tar.gz" }
  + s.source = { :http => "${TFL_DOWNLOAD_URL}" }
  s.summary = 'TensorFlow Lite'
  s.description = <<-DESC
  