Update docs - handle the error - failed to prepare device for development

[unfor19]

Thank you very much for this!

Specs

I'm on Xcode 14beta1, and I downloaded the support files for iOS 16.0
My physical device is iPhone 13 Pro with iOS 16.0 installed.

Issue

I followed the instructions in the README, and after I closed and opened Xcode, instead of getting "unsupported device" I got failed to prepare device for development in Xcode

Solution

My device was connected during the installation process, so I closed Xcode, disconnected my device, opened Xcode and then everything worked.

Suggestion

-5. Reopen Xcode;
+5. Disconnect any physical target device (iPhone, iPad, etc.)
+6. Reopen Xcode;
+7. (Optional) Connect physical target device

[filsv]

@unfor19 Thanks, added.