Patched for Audio example - Add status check when DFSDM's filter and channel de-init.

Dependents:   DISCO_F413ZH-AUDIO-demo

The base repository is https://os.mbed.com/teams/ST/code/BSP_DISCO_F413ZH/. I've just added workaround patch for Audio-in demo on DISCO_F413ZH board(Microphone U16, U17)

no such method: requests