* Set taskfile flags for REQ_TYPE_ATA_TASKFILE requests before
adding the request to the queue.
* Cleanup execute_drive_cmd().
* Remove unnecessary writes to HOB taskfile registers when using
LBA48 disk for the following cases:
- Power Management requests
(WIN_FLUSH_CACHE[_EXT], WIN_STANDBYNOW1, WIN_IDLEIMMEDIATE commands)
- special commands (WIN_SPECIFY, WIN_RESTORE, WIN_SETMULT)
- Host Protected Area support (WIN_READ_NATIVE_MAX, WIN_SET_MAX)
- /proc/ide/ SMART support (WIN_SMART with SMART_ENABLE,
SMART_READ_VALUES and SMART_READ_THRESHOLDS subcommands)
- write cache enabling/disabling in ide-disk
(WIN_SETFEATURES with SETFEATURES_{EN,DIS}_WCACHE)
- write cache flushing in ide-disk (WIN_FLUSH_CACHE[_EXT])
- acoustic management in ide-disk
(WIN_SETFEATURES with SETFEATURES_{EN,DIS}_AAM)
- door (un)locking in ide-disk (WIN_DOORLOCK, WIN_DOORUNLOCK)
- /proc/ide/hd?/identify support (WIN_IDENTIFY)
- ACPI _GTF taskfiles
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>