Harris CX/UX support, from Bob Rusk (rrusk@mail.csd.harris.com).

	Harris CX/UX support, from Bob Rusk (rrusk@mail.csd.harris.com).
	* configure.in (m88*-harris-cxux*): New configuration.
	* cxux-nat.c, config/m88k/cxux.mh, config/m88k/cxux.mt,
	config/m88k/xm-cxux.h, config/m88k/tm-cxux.h, config/m88k/nm-cxux.h:
	New files.
	* config/m88k/tm-m88k.h: Add comment about Harris OS.
	(TARGET_WRITE_PC): Pass pid through to register writers.

	* configure.in (m68*): Put vendor-only-specified host configs
	after vendor-and-os-specified configs.
	(m68*-atari-sysv4*, m68*-cbm-sysv4*): Replace with m68*-*-sysv4.