Export techpack/audio uapi headers of msm 4.14 kernel

 * With the techpack integration implementation of Google's msm-4.14
   kernel https://bit.ly/2WqiMFx (CAF didn't port this to their kernel
   thus suppose Google's port is the standard one), these headers are
   installed to include/audio/include/uapi.
 * This fixes building audio HAL with 4.14 kernel

Change-Id: I8283699470a7bcb31c771c9aa770a825b4e82519