hal: fix incorrect initial VOIP volume

VOIP playback volume could be set early before stream started,
this is ignored since the path is inactive at this time. Later
when playback path is set up, no initial volume will be applied
and default maximum value could be used, which makes VOIP sound
heard at maximum volume.
Fix this by resetting the volume after path is set up to ensure
the initial volume passed from AF can take effect.

CRs-Fixed: 2102960

Change-Id: Ic7809d42cdf59a86870f102414fb01e49dbc803d