Register png/jpeg for skpbench

Change-Id: I3dad4883a1b6d9866f7aeb89e693762750e2bc64
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/1138316
Auto-Submit: Kaylee Lubick <kjlubick@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Kaylee Lubick <kjlubick@google.com>
2 files changed