audiopolicy: audioflinger: manage stream patch volume

AudioPolicy used to hide activity of stream patch to prevent changing
the volume.
This CL replaces the filtering of the stream patch activity on the policy
by a full volume range within audio flinger.
It updates also product strategies example for automotive to add associated
strategy and full range volume.

Bug: 130284799
Test: make

Signed-off-by: François Gaffie <francois.gaffie@renault.com>
Change-Id: I6e77dc2cbed0289f0a1341f7597b1c25abee5f7d