More cutover to system.h:

More cutover to system.h:

        * Makefile.in (cppalloc.o, cpperror.o, cppexp.o, cpphash.o,
        cpplib.o, cppmain.o, fix-header.o, gcov.o, gen-protos.o,
        gengenrtl.o, halfpic.o, hash.o, scan-decls.o, scan.o): Depend on
        system.h.
        * cpphash.c: Include config.h.
        * cppalloc.c: Include system.h.  Add parameters to various
        function prototypes.
        * cpperror.c: Likewise.
        * cppexp.c: Likewise.
        * cpphash.c: Likewise.
        * cpplib.c: Likewise.
        * cppmain.c: Likewise.
        * fix-header.c: Likewise.
        * gcov.c: Likewise.
        * gen-protos.c: Likewise.
        * gengenrtl.c: Likewise.
        * halfpic.c: Likewise.
        * hash.c: Likewise.
        * scan-decls.c: Likewise.
        * scan.c: Likewise.

From-SVN: r18911