Merge "mmap write/read returns non-zero when writing successfully" am: 1a327c2ef6 am: d514bcd20d am: 7d684856a2

Original change: https://android-review.googlesource.com/c/platform/external/tinyalsa/+/1519780

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I74afaf4cb94748e116f62af3409f566248c4babf