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

A CPU job is a type of job that performs operations that requires CPU
intervention. A reset timestamp job is a job that resets the timestamp
queries based on the value offset of the first query. 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 reset timestamp job. This user extension will allow the creation of
a CPU job that resets the timestamp value in the timestamp BO and resets
the availability syncobj.

Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231130164420.932823-16-mcanal@igalia.com