USB: quirk PLL power down mode

On some AMD 700 series southbridges, ISO OUT transfers (such as audio
playback through speakers) on the USB OHCI controller may be corrupted
when an A-Link express power saving feature is active.

PLL power down mode in conjunction with link power management feature
L1 being enabled is the bad combination ... this patch prevents them
from being enabled when ISO transfers are pending.

Signed-off-by: Crane Cai <crane.cai@amd.com>
Signed-off-by: Libin Yang <libin.yang@amd.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>