Add UI next to green debug start button to select debug target device

Adding a debug target device drop-down list next to green debug start button would make device selection much more intuitive to users.

See attached Xcode screenshots for general UI concept.

Background:
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I spent much time trying to figure out why Qt Creator could debug with my iPhone device but not my iPad device. I thought it might be a provisioning issue. However, Xcode could easily switch between the two devices and debug with either device.

I expected device selection to be done under Preferences->Devices. The Devices list showed my iPad "Current state" as green and "Ready to Use" however I was not allowed to start debugging. "Set as Default" did not help.

Eventually with help from the Qt Interest list another user helped me solve my problem. I did not expect that I should have gone to:
1 - Preferences->Build & Run->Kits
2 - Select the corresponding kit that I was trying to debug iphoneos-clang
3 - Select Device under the combo box