audio HAL: fix presentation position reporting for A2DP when suspended

Ouput streams routed to A2DP must continue reporting estimated
rendered framecount when A2DP path is suspended. Audioflinger relies
on it to properly mark paused and stopped tracks as fully rendered.
When suspending, the pcm front end may return an error during write
causing the pcm driver to be closed and not reopened due to the
suspended state.
For compressed frontend, the expected behavior is that the
compressed driver stays open while A2DP is suspended.

Bug: 136446343
Test: receive a call with BT headset connected and verify that active
media tracks are properly paused

Change-Id: I5ac01d01bee35cca1edb5f05d5603bd30ea84212
(cherry picked from commit 2262125f775a7ac9c70e0e18f22e0961fd73e09c)