AudioPolicyManager: Update StreamDescriptor dump to fix warning/build break

Fix for partner-q-fs-release-generic-fs mini_arm64-userdebug
which doesn't define USE_XML_AUDIO_POLICY_CONF.
This define must be removed otherwise StreamDescriptor.cpp
isn't compiled.

Test: compile with removed USE_XML_AUDIO_POLICY_CONF
Bug: 117574496
Change-Id: Ic196739ed26b81092d14fbc2779b89a7ec9ecba8