[patch] Implement reboot via ACPI

[VinDuv]

This patchs adds support for ACPI based reboot.
This is necessary on my MacBookPro, which is reluctant to both keyboard controller and triple fault-based reboot methods ;-)
BTW, Linux (2.6.30) suffers the same issue — it hangs after printing "machine restart" unless I add "reboot=pci" to the kernel arguments.

[korli]

A few comments:

• set_reset_register isn't a good name IMO, why not reboot?
• an error message if the reset failed should be printed, one if the return status is different of OK, one in case of success after the snooze.
• acpi_reboot and acpi_shutdown can probably be factorized

[VinDuv]

Replying to korli:

A few comments:

• set_reset_register isn't a good name IMO, why not reboot?

No reason ;) I was going to call it "reset", but thought it could be confusing. "reboot" is probably fine, though.

• an error message if the reset failed should be printed, one if the return status is different of OK, one in case of success after the snooze.
  

• acpi_reboot and acpi_shutdown can probably be factorized

Good point. New patch attached.

[korli]

Edited and committed in hrev33135. Thanks!

[korli]

I changed to use AcpiReset() in hrev34658. I hope it's still OK.