Audio V4: Send volume and duplicated track attr in update metadata

Only the volume of MMAP thread was previously sent and
the attributes of duplicated tracks were skipped.

Bug: 38184704
Bug: 69623109
Test: check that the HAL receives correct track metadata volume
Test: check that the HAL receives correct duplicated track metadata
Signed-off-by: Kevin Rocard <krocard@google.com>

Change-Id: I1e3b14edd8c9a5a65d2b9f4cf8660997c81c701c