Eliminating gcc warnings.

src/sbbs3/scfg/scfg.c

src/sbbs3/scfg/scfg.h

src/sbbs3/scfg/scfgchat.c

src/sbbs3/scfg/scfgnode.c

src/sbbs3/scfg/scfgsub.c

src/sbbs3/scfg/scfgsys.c

src/sbbs3/scfg/scfgxtrn.c