all: remove unused functions from includes

Signed-off-by: Mahyar Koshkouei <mk@deltabeard.com>

include/wav.h

@@ -1,44 +1,4 @@
 #include <stdint.h>
 #include "playback.h"
 
-/**
- * Set decoder parameters for WAV.
- *
- * \param	decoder Structure to store parameters.
- */
 void setWav(struct decoder_fn* decoder);
-
-/**
- * Initialise WAV playback.
- *
- * \param	file	Location of WAV file to play.
- * \return			0 on success, else failure.
- */
-int initWav(const char* file);
-
-/**
- * Get sampling rate of Wav file.
- *
- * \return	Sampling rate.
- */
-uint32_t rateWav(void);
-
-/**
- * Get number of channels of Wav file.
- *
- * \return	Number of channels for opened file.
- */
-uint8_t channelWav(void);
-
-/**
- * Read part of open Wav file.
- *
- * \param buffer	Output.
- * \return			Samples read for each channel.
- */
-uint64_t readWav(void* buffer);
-
-/**
- * Free Wav file.
- */
-void exitWav(void);