* Roll garnet to b3ba6b6d6ab8ef658278cc43c9f839a8a8d1718e

Also includes a buildroot patch to pick up new dependency:
  build/config/fuchsia/sdk.gni

This fixes a build breakage in
garnet/public/lib/fxl/strings/string_view_unittest.cc wherein a variable
'sw5' was declared but the test erroneously tested against 'sw4' from
the previous test.

* Update license script for garnet

Reflects structural changes in directories we do not depend on. This
filters out the following directories in addition to what was already
filtered:
  garnet/drivers
  garnet/packages
  garnet/public/build/
  garnet/public/rust/

* Update licenses