term/at_keyboard.c / 8042 probe and bailout.

[Melki Christian (consultant)]

Hi.

Modern machines might not have an 8042 controller (or emulated one) listening 
at port 60/64.
The current code assumes that the controller exists if you have inserted the 
module and activated the terminal.
This behaviour causes GRUB to hang on one of my Core i7 machines.
A backoff at failure -> dead terminal or bailout at probe would be a better 
solution.

Regards,
Christian