* stack.c (parse_frame_specification): Parse as many arguments

* stack.c (parse_frame_specification):  Parse as many arguments
as there are (up to MAXARGS).  Pass all of them in argc, argv
format to SETUP_ARBITRARY_FRAME.  Put the burden of checking how
many there were, onto SETUP_ARBITRARY_FRAME.
* tm-mips.h, tm-sparc.h:  Corresponding changes.
* mips-tdep.c, sparc-tdep.c:  Ditto.