* Makefile.in (GEN_PROTOS_OBJS): Remove libcpp.a.
(gen_protos.o): Don't depend on cpplib.h or cpphash.h.
(fix-header.o): Don't depend on cpphash.h.
* scan.c (hashstr): New function.
* scan.h: Prototype it.
* fix-header.c: Don't include cpphash.h. Use hashstr.
* gen-protos.c: Don't include cpphash.h or cpplib.h. Use
hashstr. Report hash table statistics. Add private
definition of xrealloc.