Remove redundant NOTICE symbolic link.

Now that http://aosp/1235427 and http://aosp/1238719 are in, NOTICE
symbolic links are no longer needed.

Bug: 67772237
Bug: 68860345

Test: manually built and diffed before and after system image notices
Change-Id: Ib8932451b9a842ad77ad44a2e203818b1ff63c7e