The current snd-hda-intel driver seems blocking the power-off on some
devices like eeepc. Although this is likely a BIOS problem, we can add
a workaround by disabling IRQ lines before power-off operation.
This patch adds the reboot notifier to achieve it.
The detailed problem description is found in bug#11889:
http://bugme.linux-foundation.org/show_bug.cgi?id=11889
Tested-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br>
Cc: stable@kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>