//https://stackoverflow.com/questions/51215836/ios-12-not-supported-by-xcode-9-4-could-not-locate-device-support-files

//Follow below step.

//1) Unzipped downloaded file

//2) Right click on Xcode and click on Show Package Content

//3) Then paste your file on path

//Contents -> Developer -> Platforms -> iPhoneOS.platforms -> DeviceSupport

//4) Restart Xcode

//Download Files here
>//https://github.com/IMHitesh/iOS-DeviceSupport/wiki
or orignal link >//https://github.com/iGhibli/iOS-DeviceSupport