remove misspelling

- follow-up to https://skia-review.googlesource.com/c/skia/+/1081036

Change-Id: I822bd75a6cfe6fd43b40040577deb94a4b146933
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/1091921
Reviewed-by: Florin Malita <fmalita@google.com>
Reviewed-by: Eric Boren <borenet@google.com>
Commit-Queue: Mike Reed <mike@reedtribe.org>