virtio-gpu: Register capsets dynamically

virtio-gpu: Register capsets dynamically

virtio_gpu_virgl_get_num_capsets will return "num_capsets", but we can't
assume that capset_index 1 is always VIRGL2 once we'll support more capsets,
like Venus and DRM capsets. Register capsets dynamically to avoid that problem.

Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Signed-off-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Message-Id: <20241024210311.118220-13-dmitry.osipenko@collabora.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>