libgsmhr1: update for TW-TS-002 version 1.2.0 The component of libgsmhr1 being changed is RTP input functions; the change is accepting FT=1 (invalid SID) frames both with and without payload data bits.

/*
 * This header file declares the interface to our helper function
 * for writing 16-bit linear PCM samples to WAV output file.
 */

extern void write_pcm_to_wav(void *wav, const int16_t *pcm);