Revert "SPI code added (experimental)"

This reverts commit 16759c4dd5.

include/spisend.h

@@ -1,34 +1,9 @@
 #ifndef _SPISEND_H
 #define _SPISEND_H
 
-#include "globals.h"
-#include "spi.h"
-
 extern TaskHandle_t SpiTask;
 extern QueueHandle_t SPISendQueue;
 
-/*
- * Process data in SPI send queue
- */
 void spi_loop(void *pvParameters);
 
-/*
-* initialize local SPI wire interface
-*/
-void hal_spi_init();
-
-/*
- * Perform SPI write transaction on local SPI wire interface
- *   - write the command byte 'cmd'
- *   - write 'len' bytes out of 'buf'
- */
-void hal_spi_write(uint8_t cmd, const uint8_t* buf, int len);
-
-/*
- * Perform SPI read transaction on local SPI wire interface
- *   - read the command byte 'cmd'
- *   - read 'len' bytes into 'buf'
- */
-void hal_spi_read(uint8_t cmd, uint8_t* buf, int len);
-
 #endif