Fix prototype syntax for functions with no parameters in include files

Add some overlooked function prototypes  to xxxdefs.h include files
Add missing #include of relevant xxxdefs.h in a couple of source files
Add prototypes in standalone programs to silence (some) -Wmissing-prototype warnings
Remove duplicate prototype from hardrtn.c

	modified:   inc/commondefs.h
	modified:   inc/dirdefs.h
	modified:   inc/dspifdefs.h
	modified:   inc/dspsubrsdefs.h
	modified:   inc/etherdefs.h
	modified:   inc/gcmain3defs.h
	modified:   inc/initdspdefs.h
	modified:   inc/initkbddefs.h
	modified:   inc/keyeventdefs.h
	modified:   inc/maindefs.h
	modified:   inc/osmsgdefs.h
	modified:   inc/testtooldefs.h
	modified:   inc/timerdefs.h
	modified:   inc/unixfork.h
	modified:   inc/uraiddefs.h
	modified:   inc/vmemsavedefs.h
	modified:   inc/xcursordefs.h
	modified:   inc/xlspwindefs.h
	modified:   src/arith2.c
	modified:   src/ether.c
	modified:   src/hardrtn.c
	modified:   src/keytstno.c
	modified:   src/setsout.c
	modified:   src/tstsout.c

inc/osmsgdefs.h

@@ -1,8 +1,8 @@
 #ifndef OSMSGDEFS_H
 #define OSMSGDEFS_H 1
-void mess_init();
-void mess_reset();
+void mess_init(void);
+void mess_reset(void);
 LispPTR mess_read(LispPTR *args);
-LispPTR mess_readp();
-LispPTR flush_pty();
+LispPTR mess_readp(void);
+LispPTR flush_pty(void);
 #endif