Revert "audio: audio_hw.c: re-enable in-call amr-wb switch"

unstable

This reverts commit e9fdf7747b40c630e7ef26f2476aa62241aab428.
audio: audio_hw.c: temp. workaround to fix call quality issues

this isn't a proper fix and kills chinese modems, but should work perfect on all non-chinese ones

@gekkehenkie11 idea