[BUG] AudioService: fix stategy/groups attributes introspection

Strategies/volume groups are based on attributes to be identified.
Some strategies/groups rely only on AudioAttributes flags to be
identified (e.g. BLUETOOTH SCO).
AudioAttributes#Builder#setFlags has been enforced to prevent
from public API setting non public flags.
However, from JNI introspection API, it is required to be able to
set all flags.

This CL fixes this by using replaceFlags API in AudioAttributes.

Signed-off-by: Francois Gaffie <francois.gaffie@renault.com>
Change-Id: I8492e8ddcb8eb0d03bbb2a539a631694b3f64196