[MooreToCore] Fix parse error for parameter

[mingzheTerapines]

Fix parser error like this. Parser will find type after the ":", while I naming parameter with "@typekind:name". So replace ":" with "_" will solve this problem.

[uenoku]

Why are we adding inner symbols to constants in the first place 🤔 ?

[mingzheTerapines]

@uenoku , SystemVerilog provides three elaboration-time constants: parameter, localparam, and specparam. Conversation should not lose these key words, so I added it at the firstplace, which won't duplicate with each other.

[fabianschuiki]

If I recall correctly, the idea is to have the MooreToCore lowering preserve the constants as hw.wire such that they show up in simulations. It's pretty hacky. Ideally we'd do this with a dbg.variable, but there isn't very good support for those in Arcilator and other CIRCT lowerings yet.

[fabianschuiki]

Fix LGTM!