PR #64619: shlo_ref: Disable legacy code build
PR #64619: shlo_ref: Disable legacy code build

Imported from GitHub PR https://github.com/tensorflow/tensorflow/pull/64619

The code under shlo/legacy is useful for reference, but cannot build with the oss toolchains. This PR disables those targets with the no_oss tag.
Copybara import of the project:

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d87b5650899ff9d0f5eb791a7b15f7bfc9f4b4c7 by RJ Ascani <rjascani@google.com>:

shlo_ref: Disable legacy code build

The code under shlo/legacy is useful for reference, but cannot build
with the oss toolchains. This PR disables those targets with the no_oss
tag.

Merging this change closes #64619

FUTURE_COPYBARA_INTEGRATE_REVIEW=https://github.com/tensorflow/tensorflow/pull/64619 from rascani:disable_shlo_legacy_build d87b5650899ff9d0f5eb791a7b15f7bfc9f4b4c7
