Add sim only divw

Signed-off-by: Anton Blanchard <anton@linux.ibm.com>

execute1.vhdl

@@ -336,7 +336,14 @@ begin
 					if SIM = true then
 						result := ppc_divwu(e.read_data1, e.read_data2);
 						result_en := 1;
-
+					else
+						terminate_out <= '1';
+						report "illegal";
+					end if;
+				when OP_DIVW =>
+					if SIM = true then
+						result := ppc_divw(e.read_data1, e.read_data2);
+						result_en := 1;
 					else
 						terminate_out <= '1';
 						report "illegal";