* config/rs6000/aix.h: Convert CPP_PREDEFINES to
	TARGET_OS_CPP_BUILTINS.
	* config/rs6000/aix31.h: Likewise.
	* config/rs6000/aix41.h: Likewise.
	* config/rs6000/aix43.h: Likewise.
	* config/rs6000/aix51.h: Likewise.
	* config/rs6000/beos.h: Likewise.
	* config/rs6000/darwin.h: Likewise.
	* config/rs6000/eabi.h: Likewise.
	* config/rs6000/eabisim.h: Likewise.
	* config/rs6000/linux.h: Likewise.
	* config/rs6000/linux64.h: Likewise.
	* config/rs6000/lynx.h: Likewise.
	* config/rs6000/mach.h: Likewise.
	* config/rs6000/rtems.h: Likewise.
	* config/rs6000/sysv4.h: Likewise.
	* config/rs6000/vxppc.h: Likewise.

From-SVN: r55356