[Mesa-stable] Backport L3 cache control patches to 11.1

[Mark Janes]

Changes to the L3 configuration by non-mesa (eg, media) programs
interfere with mesa.  This affects media playback in ChromeOS.

Luckily, Curro made Mesa L3-aware in preparation for compute shaders.
His patches resolve media playback issues in ChromeOS.

Please backport the following commits to 11.1:

5912da45a69923afa1b7f2eb5bb371d848813c41
i965: Define symbolic constants for some useful L3 cache control registers.

50c2713726f007b988502ed5e7073fae11409853
i965: Adjust gen check in can_do_pipelined_register_writes

4841cab01a2a6d308c00b4039f1fb1a29e44ed74
i965: Keep track of whether LRI is allowed in the context struct.

2405b75bc9c6b9fa9583e926bca313ed89911bc7
i965: Define state flag to signal that the URB size has been altered.

a403ad4f5a034e52a3cd845e91c4aa3e6927b731
i965: Add slice count to the brw_device_info structure.

b22bebe9669750aac8db5057d10026cf21309339
i965: Import tables enumerating the set of validated L3 configurations.

6907175a4f682074cb7e0662598848b6f06a8e52
i965: Implement programming of the L3 configuration.

fa043698d2f6c2e4b6a4993dfeab8f0d00c33e77
i965/hsw: Enable L3 atomics.

fa1300f75e80f32a0fd40ed53cfdeaecc4c2f012
i965: Implement selection of the closest L3 configuration based on a vector of weights.

95ad0bd33ba491c2e34ce02f4ec2d75ffffe16ea
i965: Calculate appropriate L3 partition weights for the current pipeline state.

acc77947ca623472f9c7464553496314b57654ac
i965: Implement L3 state atom.

09d9638dd04ae7d34d331cb7af0bc5888f48806f
i965: Add debug flag to print out the new L3 state during transitions.

1fc797e8e408522cfbd3fa9f81d4fb33acccb034
i965: Work around L3 state leaks during context switches.

228d5a3f75086e92aaa01619a55d6c8ac7841e0e
i965: Hook up L3 partitioning state atom.

3dc97a158662d59b5b9163b34f0245bcf86219f4
i965: Document inconsistent units the URB size is represented in.


Additionally, a403ad requires the slice count for KBL.  Please apply to
11.1:
f2c891353609b48459f27f205407d42823dd7d03
Add missing platform information for KBL


Once these patches are applied, we will be requesting a 11.1.2 release.

thanks,

Mark Janes