Summary:
This adds the vectorized ChaCha20 implementation from HACL* to NSS and replaces the old vectorized code.
Note that this is not used on Android as we currently have no way of testing this for Android or use it on Android for Firefox.

Reviewers: ttaubert

Reviewed By: ttaubert

Bug #: 1424663

Differential Revision: https://phabricator.services.mozilla.com/D467

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extra : histedit_source : 4d998bcb0c41fb703182455eaf5acf1b2e53a2e0%2C16cfd6e35aaab7cb0f1d9487d6ca0d392b04c1b3