Added support for MUL/DIV (Passes all tests)

rtl/vortex.v

@@ -38,7 +38,7 @@ wire[31:0] decode_rd1;
 wire[4:0]  decode_rs2;
 wire[31:0] decode_rd2;
 wire[1:0]  decode_wb;
-wire[3:0]  decode_alu_op;
+wire[4:0]  decode_alu_op;
 wire       decode_rs2_src; 
 reg[31:0]  decode_itype_immed; 
 wire[2:0]  decode_mem_read; 
@@ -59,7 +59,7 @@ wire[4:0]  d_e_rs1;
 wire[31:0] d_e_rd1;
 wire[4:0]  d_e_rs2;
 wire[31:0] d_e_rd2;
-wire[3:0]  d_e_alu_op;
+wire[4:0]  d_e_alu_op;
 wire[1:0]  d_e_wb;
 wire       d_e_rs2_src;
 wire[31:0] d_e_itype_immed;