ata: libata-core: Disable READ LOG DMA EXT for Samsung 840 EVOs

ata: libata-core: Disable READ LOG DMA EXT for Samsung 840 EVOs

Samsung' 840 EVO with the latest firmware (EXT0DB6Q) locks up with
the a message: "READ LOG DMA EXT failed, trying PIO" during boot.

Initially this was discovered because it caused a crash
with the sata_dwc_460ex controller on a WD MyBook Live DUO.

The reporter "Tice Rex" which has the unique opportunity that he
has two Samsung 840 EVO SSD! One with the older firmware "EXT0BB0Q"
which booted fine and didn't expose "READ LOG DMA EXT". But the
newer/latest firmware "EXT0DB6Q" caused the headaches.

BugLink: https://github.com/openwrt/openwrt/issues/9505
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>