audio policy: allow disabling A2DP for media.

Added FORCE_NO_BT_A2DP forced use to allow applications to
override default policy to use A2DP whenever connected.

Bug 6485897.

Change-Id: I0039232ea6cce4121f375961b2c153d1a0d92e49
diff --git a/include/system/audio_policy.h b/include/system/audio_policy.h
index 57f7110..91b8e9c 100644
--- a/include/system/audio_policy.h
+++ b/include/system/audio_policy.h
@@ -42,6 +42,7 @@
     AUDIO_POLICY_FORCE_BT_DESK_DOCK,
     AUDIO_POLICY_FORCE_ANALOG_DOCK,
     AUDIO_POLICY_FORCE_DIGITAL_DOCK,
+    AUDIO_POLICY_FORCE_NO_BT_A2DP, /* A2DP sink is not preferred to speaker or wired HS */
 
     AUDIO_POLICY_FORCE_CFG_CNT,
     AUDIO_POLICY_FORCE_CFG_MAX = AUDIO_POLICY_FORCE_CFG_CNT - 1,