audio:Changes to enable LPA/Tunnel

 Changes to enable LPA/Tunnel mode

Change-Id: Ic7381c4c45b67ae0cfdcc4a01fc85014ca95dec2
libhardware_legacy: Add MSM specific flags, devices and channels.

- Add support for MSM flags, devices and channels

Change-Id: I6cb5f34b49e24e6d6f97821189bdb6e96ce283a8
audio: Add ifdefs for MSM specific flags

* Require QCOM_HARDWARE to enable these flags.

Change-Id: Ia20602ac31d7e192c71b48ad21d4112d5af273c6
audio: Add ifdefs for LPA/Tunnel

* Require QCOM_DIRECTTRACK to enable this feature.

Change-Id: I8d698b7fef6da09378a965be1f500de2eacce7c9