Redo the types in bilerp_clamp_8888 to make more sense

Cleanup:
  Remove two unused from_8888

Change-Id: Ib87986a122169154e493d489fd1d24718c28f5c7
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/453638
Commit-Queue: Herb Derby <herb@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
1 file changed