gfio: drop support for high/low priority latency results

gfio: drop support for high/low priority latency results

High/low priority latencies have been replaced by a per prio array.
This allows us to have latency results for more than just two priorities.

Unfortunately this currently means that we have to drop the support for
visualizing the high/low priority latencies.

If someone wants to know the per prio latency results, both the regular
output and the json output contain this information.

The GUI could be extended to support the new per priority format at a
later time, if anyone has a huge need for this feature.

Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Link: https://lore.kernel.org/r/20220203192814.18552-17-Niklas.Cassel@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>