iOS qt-cmake output is not informative when xcode has been updated.

According to documentation iOS xcodeproject is generated with qt-cmake from the iOS binary folder inside Qt kit:

https://doc.qt.io/qt-6/ios.html

Now, if XCode has been updated, it waits for user action thus xcode-select (which the cmake script is invoking) will report error:

jarkovihriala@Jarkos-MacBook-Pro SimpleEffectComposerDemo % ~/Qt/6.8.0/ios/bin/qt-cmake .

CMake Error at /Users/<user>/Qt/Tools/CMake/CMake.app/Contents/share/cmake-3.29/Modules/Platform/iOS-Initialize.cmake:4 (message):

  iphoneos is not an iOS SDK

Call Stack (most recent call first):

  /Users/<user>/Qt/Tools/CMake/CMake.app/Contents/share/cmake-3.29/Modules/CMakeSystemSpecificInitialize.cmake:34 (include)

  CMakeLists.txt:7 (project)

This is resolved by

1. Opening XCode
2. Agreeing possible dialogs
3. Making sure recent iOS kit has been downloaded by the xcode.

Without these, the qt-cmake script won't run. The information on the output should indicate that xcode tools are operational and user must open xcode for more information.

ping vilavoniu