fixed modelsim compile error

boards/uniboard2a/designs/unb2a_led/src/vhdl/unb2a_led.vhd

@@ -163,7 +163,7 @@ BEGIN
   led_flash_green <= sel_a_b(g_factory_image=FALSE, led_flash, '0');
 
 
-  u_extend : common_lib.common_pulse_extend
+  u_extend : ENTITY common_lib.common_pulse_extend
   GENERIC MAP (
     g_extend_w => 22 -- (2^22) / 50e6 = 0.083886 th of 1 sec
   )
@@ -198,7 +198,7 @@ BEGIN
     pulse_out      => pulse_10Hz
   );
 
-  u_extend_10Hz : common_lib.common_pulse_extend
+  u_extend_10Hz : ENTITY common_lib.common_pulse_extend
   GENERIC MAP (
     g_extend_w => 21 -- (2^21) / 50e6 = 0.041943 th of 1 sec
   )

boards/uniboard2a/designs/unb2a_led/tb/vhdl/tb_unb2a_led.vhd

@@ -38,7 +38,7 @@
 --
 --
 
-LIBRARY IEEE, common_lib, unb2a_board_lib, ;
+LIBRARY IEEE, common_lib, unb2a_board_lib;
 USE IEEE.std_logic_1164.ALL;
 USE IEEE.numeric_std.ALL;
 USE common_lib.common_pkg.ALL;