Eliminate unused code.

src/sbbs3/scfg/Attic/scfgxfr2.c

src/sbbs3/scfg/scfg.c

src/sbbs3/scfg/scfgmsg.c

src/sbbs3/scfg/scfgnode.c

src/sbbs3/scfg/scfgsub.c

src/sbbs3/scfg/scfgsys.c

src/sbbs3/scfg/scfgxfr2.c