[LSC] Add LOCAL_LICENSE_KINDS to external/libaom

Added SPDX-license-identifier-BSD to:
  libaom/third_party/libwebm/Android.mk

Added SPDX-license-identifier-BSD SPDX-license-identifier-ISC
    SPDX-license-identifier-MIT legacy_reciprocal legacy_unencumbered
to:
  Android.bp

Bug: 68860345
Bug: 151177513
Bug: 151953481

Test: m all

Exempt-From-Owner-Approval: janitorial work
Change-Id: Ie07920134f66b445b6d860be1308c66fac5a8829