Merge "Revert "sync ptr before get mmap avail"" am: 713a5ed6f0 am: e768554643 am: 1a146e13b4

Original change: https://android-review.googlesource.com/c/platform/external/tinyalsa/+/1519783

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I22cddb90593902e5cee466c3f44a67a63b23fec7