app/compress-perf: prevent output buffer overflow

app/compress-perf: prevent output buffer overflow

This patch fixes the issue of memory overwrite after the end of
the output buffer by calculating its size as the number of all
segments multipled by the output segment size.
Additionally buffer overflow errors returned by PMD driver are
detected and shown, ending the test.

Also the output buffer size multiplier was increased from 105%
to 110% to allow running the tests on noncompressible files that
expand to over 107% of original size during the compression.

The changes were made in the verification part of the flow and
they don't affect the benchmark results.

Fixes: 424dd6c8c1 ("app/compress-perf: add weak functions for multicore test")

Signed-off-by: Adam Dybkowski <adamx.dybkowski@intel.com>
Acked-by: Fiona Trahe <fiona.trahe@intel.com>