herolte: use voice_control_with_okgoogle for hotword detection

    * According to OSS audio hal sources, the voice-rec-mic path is used
      for doing voice recognition, e.g. hotword detection (which in our
      use case is OK Google). Previously we were using the
      recording-mic path from stock mixer_paths{gains}.xml which is
      virtually wrong as that path is not meant for hotword detection,
      but for voice recording. Since stock mixer_paths{gains}.xml
      exposes values for performing OK Google hotword detection, use
      them which are more appropriate for our use case.

    * Configurations taken from stock G930FXXU8ETI2

Change-Id: Ic6b157dbcfb7a3b49094fa8818da72ce6c5bf40f