net: tehuti: remove unused inline function bdx_tx_db_size

There's no callers in-tree anymore.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/tehuti/tehuti.c

@@ -1362,18 +1362,6 @@ static void print_rxfd(struct rxf_desc *rxfd)
  * As our benchmarks shows, it adds 1.5 Gbit/sec to NIS's throuput.
  */
 
-/*************************************************************************
- *     Tx DB                                                             *
- *************************************************************************/
-static inline int bdx_tx_db_size(struct txdb *db)
-{
-	int taken = db->wptr - db->rptr;
-	if (taken < 0)
-		taken = db->size + 1 + taken;	/* (size + 1) equals memsz */
-
-	return db->size - taken;
-}
-
 /**
  * __bdx_tx_db_ptr_next - helper function, increment read/write pointer + wrap
  * @db: tx data base