Don't declare things in more than one place. Move some declarations

between headers.  Code is now fully prototyped and compiles cleanly
with gcc -Wstrict-prototypes -Wmissing-prototypes -Wnested-externs
-Wredundant-decls.  Closes #723788.

src/lib/lwp/lwpint.h

@@ -85,7 +85,6 @@ typedef struct {
 /* internal routines */
 void lwpAddTail(struct lwpQueue *, struct lwpProc *);
 struct lwpProc *lwpGetFirst(struct lwpQueue *);
-void lwpReschedule(void);
 void lwpReady(struct lwpProc *);
 void lwpOnalarm(void);