message: Clarify that iOS flex prebuilt does not support x86_64
diff: @@ -133,8 +133,13 @@ dependencies {
  #### Using CocoaPods
  -We provide nightly prebuilt select TF ops CocoaPods, which you can depend on
  -alongside the `TensorFlowLiteSwift` or `TensorFlowLiteObjC` CocoaPods.
  +We provide nightly prebuilt select TF ops CocoaPods for `armv7` and `arm64`,
  +which you can depend on alongside the `TensorFlowLiteSwift` or
  +`TensorFlowLiteObjC` CocoaPods.
  +
  +*Note*: If you need to use select TF ops in an `x86_64` simulator, you can build
  +the select ops framework yourself. See [Using Bazel + Xcode](#using_bazel_xcode)
  +section for more details.
  ```ruby
  # In your Podfile target:
  