Cleanup SkQP code for dumping GPU info

Change-Id: Ifb6ab8c05d4a1dfd107289edb700280271afe2fb
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/566337
Commit-Queue: Derek Sollenberger <djsollen@google.com>
Reviewed-by: Leon Scroggins <scroggo@google.com>
3 files changed