[Intel-gfx] [PATCH i-g-t v4 0/7] CRC testing with Chamelium improvements

[Paul Kocialkowski]

Changes since v3:
* Renamed structure used by async crc calculation for more clarity
* Used const qualifier for untouched buffer when hashing
* Split actual calculation to a dedicated function
* Reworked async functions names for more clarity
* Reworked descriptions for better accuracy
* Exported framebuffer cairo surface and use it directly instead of
  (unused) png dumping
* Fix how the framebuffer cairo surface is obtained to avoid destroying
  it too early