iris: Change the validation list debug code to print the BO list instead

iris: Change the validation list debug code to print the BO list instead

This code assumed that batch->exec_bos[i] matched validation_list[i],
which won't be true once we start suballocating BOs.  This patch changes
it to print the full exec_bos[i] list instead of the validation list,
as that has the logical list of objects, names, addresses, placement,
whether they are suballocated, and so on.

It may be useful to look at the actual validation list as well; I'm not
sure how common that is.  We may want to add additional debug prints in
the future.

Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/12623>