* config/alpha/alpha.h, config/arc/arc.h, config/avr/avr.h,
	config/c4x/c4x.h, config/d30v/d30v.h, config/dsp16xx/dsp16xx.h,
	config/fr30/fr30.h, config/ia64/ia64.h, config/m68hc11/m68hc11.h,
	config/mips/mips.h, config/rs6000/rs6000.h, config/sparc/sparc.h,
	config/stormy16/stormy16.h, config/v850/v850.h: Remove commented
	out target macro definitions and non-target-specific comments
	mostly taken from old versions of the manual.

From-SVN: r49033