If REAL_ARITHMETIC is defined or if LONG_DOUBLE_TYPE_SIZE
is 96, then define REAL_VALUE_ macros to invoke functions in real.c.

(REAL_VALUE_RNDZINT, REAL_VALUE_UNSIGNED_RNDZINT):
New macros truncate toward zero to integer value but
return REAL_VALUE_TYPE.

(REAL_VALUE_TO_DECIMAL): New macro defaults to
fprintf if no REAL_ARITHMETIC, otherwise uses real.c for
binary to decimal conversion.  Used in ASM_OUTPUT_ macros.

From-SVN: r3934