Simple patch to enable Message Signalled Interrupts for the HDA Intel
audio controller.  Tested with:
 Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) High Definition Audio Controller (rev 03)
MSI is better because it means audio doesn't end up sharing IRQ with USB.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>