Upgrade libopus to v1.4 am: 0475b02657 am: 5acd7d4d13 am: ae1f9df2cd am: e3ec92374e am: 0ffd05a233 am: 2b91d5739a

Original change: https://android-review.googlesource.com/c/platform/external/libopus/+/2555370

Change-Id: Ib01fb57e1b6a2d099e1fc4976631f7cabf0ac43d
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>