Add support for displaying a real parameter using %d.
Add support for displaying a real parameter using %d.

This patch modifies the real parameter get_value routine to use
the standard vpip_real_get_value() routine. This routine has
support for an integer and a decimal string value.

themperek/iverilog,CastMi/iverilog,CastMi/iverilog,themperek/iverilog,themperek/iverilog,CastMi/iverilog