This works around the too fast timer seen on some ATI boards.
I don't feel confident enough about it yet to enable it by default, but give
users the option.
Patch and debugging from Christopher Allen Wing <email@example.com>, with
minor tweaks (renamed the option and documented it)
Signed-off-by: Andi Kleen <firstname.lastname@example.org>
Signed-off-by: Andrew Morton <email@example.com>
Signed-off-by: Linus Torvalds <firstname.lastname@example.org>