drm/v3d: Create a CPU job extension for the timestamp query job

drm/v3d: Create a CPU job extension for the timestamp query job

A CPU job is a type of job that performs operations that requires CPU
intervention. A timestamp query job is a job that calculates the
query timestamp and updates the query availability by signaling a
syncobj. As V3D doesn't provide any mechanism to obtain a timestamp
from the GPU, it is a job that needs CPU intervention.

So, create a user extension for the CPU job that enables the creation
of a timestamp query job. This user extension will allow the creation of
a CPU job that performs the timestamp query calculation and updates the
timestamp BO with the proper value.

Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231130164420.932823-15-mcanal@igalia.com