(#322) fix codegen bug for multiple ports using same protocol

What this MR does / why we need it:

make skeleton for HDL worker w/ multiple ports w/ same protocol (e.g. tx_event protocol) results in codegen-induced, syntax-invalid VHDL in the worker shell.

Steps to complete before submitting MR:

• I have read Contribution guidelines

Release Notes

Changelog

bug(tools): fix codegen bug when multiple ports use the same protocol

Which issue(s) this MR closes

Closes #322 (closed)