incorrectly added as a union member which overlaid the keyboard
state structure. Fixed by moving the callout structure into to
keyboard state structure.
timeout()/untimeout() API:
- Clients supply callout handle storage, thus eliminating problems of
resource allocation.
- Insertion and removal of callouts is constant time, important as
this facility is used quite a lot in the kernel.
The old timeout()/untimeout() API has been removed from the kernel.
mhitch