* coredep.c: If NEED_SYS_CORE_H defined, include <sys/core.h>

	* coredep.c: If NEED_SYS_CORE_H defined, include <sys/core.h>
	(can't include it in nm-*.h file because it causes conflicts with
	a.out symbol definitions).
	* hp300ux-nat.c (fetch_core_registers): Commented out; obsolete.
	* config/m68k/hp300hpux.mh (NATDEPFILES): Added coredep.o and
	corelow.o.
	* config/m68k/nm-hp300hpux.h (NEED_SYS_CORE_H): Defined.
	(REGISTER_U_ADDR): Defined.
	* config/m68k/xm-hp300hpux.h (HAVE_TERMIOS): Define instead of
	HAVE_TERMIO.
	* config/pa/xm-hppah.h: Likewise.