sim: use Value.cast on traces.

See kuznia-rdzeni/coreblocks#357.

Author: wanda-phi

amaranth/sim/pysim.py

@@ -65,6 +65,7 @@ def __init__(self, fragment, *, vcd_file, gtkw_file=None, traces=()):
         trace_names = SignalDict()
         assigned_names = set()
         for trace in traces:
+            trace = Value.cast(trace)
             for trace_signal in trace._rhs_signals():
                 if trace_signal not in signal_names:
                     if trace_signal.name not in assigned_names: