purged an unused method

stepper.c

@@ -255,15 +255,6 @@ void st_synchronize()
   while(block_buffer_tail != block_buffer_head) { sleep_mode(); }    
 }
 
-// Cancel all buffered steps
-void st_flush()
-{
-  cli();
-  block_buffer_tail = block_buffer_head;
-  current_block = NULL;
-  sei();
-}
-
 // Configures the prescaler and ceiling of timer 1 to produce the given rate as accurately as possible.
 // Returns the actual number of cycles per interrupt
 uint32_t config_step_timer(uint32_t cycles)

stepper.h

@@ -37,9 +37,6 @@ void st_get_position_steps(int32_t (*vector)[3]);
 // Block until all buffered steps are executed
 void st_synchronize();
 
-// Cancel all pending steps
-void st_flush();
-
 // Execute the homing cycle
 void st_go_home();