Add license_note am: e6aed768e7 am: f00dfa3612 am: 359510f778 am: 519b19e8f0

Original change: https://android-review.googlesource.com/c/platform/external/fft2d/+/2011746

Change-Id: I0eb40f355bbfbc9cbc81fa9f54d3f79837e3ea6d