Update Wuffs version

This pulls in the Wuffs bug fix for MSVC:
https://github.com/google/wuffs/commit/ed52fdecb95fa3a55af41b20ca132665834eb8d5
"Rework how we avoid clang's -Wunused-function".

Bug: skia:8235
Bug: skia:8764
Change-Id: I890066e47f61213101b9c8822b1ec60d22584f75
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/206142
Reviewed-by: Leon Scroggins <scroggo@google.com>
Commit-Queue: Leon Scroggins <scroggo@google.com>
2 files changed