audio: Add a flag for VOIP RX

#ifdef QCOM_HARDWARE

//Qualcomm Flags

    AUDIO_OUTPUT_FLAG_LPA = 0x1000,     // use LPA

    AUDIO_OUTPUT_FLAG_TUNNEL = 0x2000   // use Tunnel

    AUDIO_OUTPUT_FLAG_TUNNEL = 0x2000,   // use Tunnel

    AUDIO_OUTPUT_FLAG_VOIP_RX = 0x4000   // use this flag in combination with DIRECT to

                                         // indicate HAL to activate EC & NS

                                         // path for VOIP calls

#endif

} audio_output_flags_t;