ahci: fix notification handling
ahci: fix notification handling

Asynchronous notification on ICH9 didn't work because it didn't write
AN FIS into the RX area - it only updates SNotification.  Also,
snooping SDB_FIS RX area is racy against further SDB FIS receptions.
Let sata_async_notification() determine using SNTF if it's available
and snoop RX area iff SNTF isn't available

Signed-off-by: Tejun Heo <ccfba69985e72fbcd9ba8bbb6db43d42971ad06d@gmail.com>
Cc: Kristen Carlson Accardi <a2bec03b708747d8f8ec0ab8d19ca0546db65231@intel.com>
Signed-off-by: Jeff Garzik <f3e731dfa293c7a83119d8aacfa41b5d2d780be9@garzik.org>

TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas