app/compress-perf: optimize operations pool allocation

app/compress-perf: optimize operations pool allocation

An array of the size of total operations needed for the de/compression is
reserved for ops while enqueueing, although only first burst_size entries
of the array are used.

Reduce the size of the array allocated.

Fixes: b68a82425da4 ("app/compress-perf: add performance measurement")
Cc: stable@dpdk.org
Signed-off-by: Raja Zidane <rzidane@nvidia.com>
Acked-by: Matan Azrad <matan@nvidia.com>
Acked-by: Fan Zhang <roy.fan.zhang@intel.com>