Compile fix

src/vme_data_bus.vhd

@@ -256,8 +256,8 @@ architecture rtl of vme_data_bus is
   constant TIMEOUT_CNT_MAX : integer := 255;
   signal timeout_cnt : integer range 0 to 255 := TIMEOUT_CNT_MAX;
 
-  signal last_ds	        : std_logic_vector(1 downto 0);
-  signal last_berr              : std_logic;
+  signal last_ds_n	        : std_logic_vector(1 downto 0);
+  signal last_berr_n              : std_logic;
   
 begin