mesa: Implement glGet*(GL_PRIMITIVE_RESTART_FOR_PATCHES_SUPPORTED).

Technically, this was introduced with GL 4.4.  However, I believe it
was intended to be retroactive.  As far as I know, AMD has never
supported primitive restart with patches, while NVidia and Intel do.
This necessitated the need for a query which would allow applications
to figure out whether this was usable or not.

I decided to expose it everywhere ARB_tessellation_shader is exposed.
(It's also in both OES and EXT_tessellation_shader.)

Enable this for i965 and Gallium drivers which expose the capability.

v2: Fix a bug in the state_tracker code (caught by Ilia Mirkin).

Bugzilla: https://cvs.khronos.org/bugzilla/show_bug.cgi?id=10364
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
6 files changed