msm7x30: update references to AUDIO_FORMAT

Based on:
https://github.com/CyanogenMod/android_hardware_qcom_audio-caf/commit/8090ad410d42a1bed58a3130ebd27d6df70a20d9

Change-Id: I8a51e6b5bcef285e54023cde6e4bb278bdc594a0