refactor: renamed top.v to riscv.v

riscv-ac.sim/sim_1/behav/xsim/tb_riscv.tcl

@@ -0,0 +1,11 @@
+set curr_wave [current_wave_config]
+if { [string length $curr_wave] == 0 } {
+  if { [llength [get_objects]] > 0} {
+    add_wave /
+    set_property needs_save false [current_wave_config]
+  } else {
+     send_msg_id Add_Wave-1 WARNING "No top level signals found. Simulator will start without a wave window. If you want to open a wave window go to 'File->New Waveform Configuration' or type 'create_wave_config' in the TCL console."
+  }
+}
+
+run 1000ns