util: use faster zlib's CRC32 implementaion

zlib provides a faster slice-by-4 CRC32 implementation than the
traditional single byte lookup one used by mesa. As most supported
platforms now link zlib unconditionally, we can easily use it.

Improvement for a 1MB buffer (avg MB/s, n=100, zlib 1.2.8):

  i5-6600K                    C2D E4500
mesa zlib                    mesa zlib
 443 1443 225% +/- 2.1%       403 1175 191% +/- 0.9%

It has been verified the calculation results stay the same after this
change.

Signed-off-by: Grazvydas Ignotas <[email protected]>
Reviewed-by: Eric Engestrom <[email protected]>
Reviewed-by: Marek Olšák <[email protected]>
Reviewed-by: Ian Romanick <[email protected]>

0 files changed, 0 insertions, 0 deletions