gallium/tools: improve handling of pointer arrays

gallium/tools: improve handling of pointer arrays

Extend the special handling of return types to also include pointer
type array list elements, so we ignore the initial "name" of the
element until we know a better type for them. This improves the type
"detection" of such pointer array elements when parsing the logs
with dump.py / tracediff.sh

Related to Mesa issue #4609

Signed-off-by: Matti Hamalainen <ccr@tnsp.org>
Acked-By: Mike Blumenkrantz <michael.blumenkrantz@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11492>