Move comment to license_note am: 826c6cb17c am: 44eaa1cd00 am: 650e398414 am: 1ad861b9aa

Original change: https://android-review.googlesource.com/c/platform/external/grpc-grpc/+/2008359

Change-Id: Ica75c4d4eb935584f8aae30fdfd2c0c5290a0dff