Fix incorrect failure handling in vinput_init

[NOVBobLee]

After class_register failure, the wrong function class_unregister was used. The correct cleanup function should be unregister_chrdev, as register_chrdev was used before class_register.

[jserv]

Thanks for spotting this issue. Can you point out more in current example code?

[NOVBobLee]

Yes, I’ll go through the current example code and point out any additional issues I find. I'll update you in a few days.

[jserv]

Thank @NOVBobLee for contributing!