emulators/simh: fix name clash with other ports and tidy compilations

[pizzamig]

Summary

emulators/simh: fix name clash with other ports and tidy compilations

Fix name clash with gri and nova, that caused conflicts
Fix compilation warnings.

PR\: 222968
Submitted by\: [e-mail] (maintainer)
Approved by\: olivier (mentor)
Approved by\: lme (mentor)

Test Plan

portlint's OK
poudriere build on 10.3 10.4 11.0 11.1 on i386 amd64