radeonsi: enable multi-draw related pipe caps
This enables GL_shader_draw_parameters and GL_ARB_indirect_parameters as well
as a properly accelerated implementation of GL_ARB_multi_draw_indirect.
Enabling the feature requires a sufficiently uptodate firmware -- those have
already been released a long time ago, although this does mean that the
feature only works with the amdgpu kernel module, since the radeon module
doesn't have a way to query the firmware version.
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>