chore(bhi160): Make bhi160_fetch_fifo() return void

bhi160_fetch_fifo() doesn't actually return any meaningful error values
anymore.  Remove return-value checks and make the function return void
to express this clearly.

Signed-off-by: Rahix <rahix@rahix.de>

epicardium/modules/bhi.c

@@ -340,7 +340,7 @@ bhi160_handle_packet(bhy_data_type_t data_type, bhy_data_generic_t *sensor_data)
  * Fetch all data available from BHI160's FIFO buffer and handle all packets
  * contained in it.
  */
-static int bhi160_fetch_fifo(void)
+static void bhi160_fetch_fifo(void)
 {
 	/*
 	 * Warning:  The code from the BHy1 docs has some issues.  This
@@ -398,7 +398,6 @@ static int bhi160_fetch_fifo(void)
 
 	hwlock_release(HWLOCK_I2C);
 	mutex_unlock(&bhi160_mutex);
-	return result;
 }
 
 /*
@@ -512,13 +511,7 @@ void vBhi160Task(void *pvParameters)
 	/* ----------------------------------------- */
 
 	while (1) {
-		int ret = bhi160_fetch_fifo();
-		if (ret == -EBUSY) {
-			LOG_WARN("bhi160", "Could not acquire mutex for FIFO?");
-			continue;
-		} else if (ret < 0) {
-			LOG_ERR("bhi160", "Unknown error: %d", -ret);
-		}
+		bhi160_fetch_fifo();
 
 		/*
 		 * Wait for interrupt.  After two seconds, fetch FIFO anyway in