Multiple OpenGL 4.x Adjustments Hits Mainline Mesa

A slew of patches hit mainline Mesa over the night that take care of various OpenGL 4.x related work items.

- First, within the Mesa state tracker, the ARB_ES3_1_compatibility extension is enabled whenever the driver supports OpenGL ES 3.1. In this case, OpenGL 4.5's ARB_ES3_1_compatibility is now turned on in Git for the RadeonSI and Nouveau NVC0 Gallium3D drivers.

- The work by Jason Ekstrand at Intel on ARB_robust_buffer_access_behavior (OpenGL 4.3) and KHR_robust_buffer_access_behavior (OpenGL 4.5) is now in Git.

- The NVC0 Nouveau GL3.txt documentation has been updated to reflect the extensions on for at least Fermi/Kepler while for now ignoring the Maxwell shortcomings.

MesaMatrix.net is now looking a lot more green this morning. As Mesa 11.3 hasn't yet been branched, this work will be found in the stable Mesa update due out in June.