rename build/ ninja/

Bazel has got dibs on BUILD.

Change-Id: I95ded7d84ffd73b277e15253a52284ddb6f4ab7d
Reviewed-on: https://skia-review.googlesource.com/c/skcms/+/304852
Auto-Submit: Mike Klein <mtklein@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
61 files changed