* real.h (REAL_MODE_FORMAT): New macro.
	* c-cppbuiltin.c, optabs.c, real.c, config/alpha/alpha.c
	* config/c4x/c4x.c, config/i370/i370.c, config/i386/freebsd.h
	* config/i386/i386.c, config/i960/i960.c, config/ia64/ia64.c
	* config/m68k/m68k.c, config/mips/mips.c, config/rs6000/rs6000.c
	* config/vax/vax.c: Use REAL_MODE_FORMAT instead of referring
	directly to real_format_for_mode array, wherever possible.

From-SVN: r72168