Added missing dp lib and test bench tb_mms_epcs.vhd.

libraries/io/epcs/hdllib.cfg

 hdl_lib_name = epcs
 hdl_library_clause_name = epcs_lib
-hdl_lib_uses = common tech_flash
+hdl_lib_uses = common dp tech_flash
 
 build_sim_dir = $HDL_BUILD_DIR
 build_synth_dir = 
@@ -10,3 +10,4 @@ synth_files =
     src/vhdl/mms_epcs.vhd
 
 test_bench_files = 
+    $UNB/Firmware/modules/epcs/tb/vhdl/tb_mms_epcs.vhd