* config/mh-a68bsd: clean out dead code
* config/mh-apollo68: clean out dead code
* config/mh-cxux: clean out dead code
* config/mh-decstation: clean out dead code
* config/mh-dgux: clean out dead code
* config/mh-dgux386: clean out dead code
* config/mh-hp300: clean out dead code
* config/mh-hpux: clean out dead code
* config/mh-hpux8: clean out dead code
* config/mh-interix: clean out dead code
* config/mh-irix4: clean out dead code
* config/mh-lynxrs6k: clean out dead code
* config/mh-mingw32: clean out dead code
* config/mh-ncr3000: clean out dead code
* config/mh-ncrsvr43: clean out dead code
* config/mh-necv4: clean out dead code
* config/mh-openedition: clean out dead code
* config/mh-riscos: clean out dead code
* config/mh-sco: clean out dead code
* config/mh-sysv4: clean out dead code
* config/mh-lynxos: removed, contained only dead code
* config/mh-vaxult2: removed, contained only dead code
* config/mh-sun3: removed, contained only dead code
* configure.in: remove references to dead files
