audiohal: Fix incompatibility with legacy hal for writes

The combo call to stream_out->write + get_presentation_position
wasn't delivering the results of these calls entirely
correctly. Since the 'WriteResult' struct was lacking the field
for returning the status of the call to
'get_presentation_position', the client could erroneously update
the presentation position to bogus values if the call to the
legacy HAL had failed.

Updated IStreamOut.WriteStatus to include the missing field,
and updated the code to fill it out.

Also fixed logspam resulting from calling a stubbed
stream_in->get_capture_position.

Bug: 30222631
Test: Loopback RTT, media CTS
Change-Id: I38ac3b01beb095e176b54608e11e71ae5d5eafb6