[automerger skipped] tinyalsa: add support for Mixer plugins am: da302cc198 am: fff4cea9bc am: d86730a0c5 -s ours

am skip reason: Change-Id I5a29eb8d7675f804c5d2f10da978f28f8c2cf134 with SHA-1 6b2537fd1b is in history

Original change: https://android-review.googlesource.com/c/platform/external/tinyalsa/+/1554366

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: Ib78c123b806ceb8d327ca4265f748970418d7751