ata: libata: move NCQ related ATA_DFLAGs

ata_dev_configure() starts off by clearing all flags in ATA_DFLAG_CFG_MASK:
dev->flags &= ~ATA_DFLAG_CFG_MASK;

ata_dev_configure() then calls ata_dev_config_lba() which calls
ata_dev_config_ncq().

ata_dev_config_ncq() will set the correct ATA_DFLAGs depending on what is
actually supported.

Since these flags are set by ata_dev_configure(), they should be in
ATA_DFLAG_CFG_MASK and not in ATA_DFLAG_INIT_MASK.

ATA_DFLAG_NCQ_PRIO_ENABLED is set via sysfs, is should therefore not be in
ATA_DFLAG_CFG_MASK. It also cannot be in ATA_DFLAG_INIT_MASK, because
ata_eh_schedule_probe() calls ata_dev_init(), which will clear all flags in
ATA_DFLAG_INIT_MASK.

This means that ATA_DFLAG_NCQ_PRIO_ENABLED (the value the user sets via
sysfs) would get silently cleared if ata_eh_schedule_probe() is called.
While that should only happen in certain circumstances, it still doesn't
seem right that it can get silently cleared.

(ata_dev_config_ncq_prio() will still clear the ATA_DFLAG_NCQ_PRIO_ENABLED
flag if ATA_DFLAG_NCQ_PRIO is suddenly no longer supported after a
revalidation.)

Because of this, move ATA_DFLAG_NCQ_PRIO_ENABLED to be outside of both
ATA_DFLAG_CFG_MASK and ATA_DFLAG_INIT_MASK.

Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>