Read and include sign of scanned decimal.
Read and include sign of scanned decimal.

Fix simple bug where negative values read from the source file were
not getting their sign. The fix was proposed in pr1876738.
themperek/iverilog,CastMi/iverilog,CastMi/iverilog,themperek/iverilog,CastMi/iverilog,themperek/iverilog