Fix for br992 - prevent assertion/crash on declarations outside a module.
Fix for br992 - prevent assertion/crash on declarations outside a module.

parse.y has been updated to allow declarations outside a module (legal
in SystemVerilog), but not all types of declaration are supported yet.
Output a sorry or error message as appropriate.

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