drm-uapi/xe: add exec_queue_id member to drm_xe_wait_user_fence structure

remove the num_engines/instances members from drm_xe_wait_user_fence structure
and add a exec_queue_id member

Right now this is only checking if the engine list is sane and nothing
else. In the end every operation with this IOCTL is a soft check.
So, let's formalize that and only use this IOCTL to wait on the fence.

exec_queue_id member will help to user space to get proper error code
from kernel while in exec_queue reset

v2: Also fix test invalid_flag (Francois Dugast)

v3: Replace -ETIME with -EIO in test_compute_mode (Brian Welty)

Signed-off-by: Bommu Krishnaiah <krishnaiah.bommu@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Francois Dugast <francois.dugast@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>