boxing_word.h: fix the error in the comment [ci skip]
MODIFY
include/mruby/boxing_word.h
include/mruby/boxing_word.h
@@ -95,13 +95,12 @@ enum mrb_special_consts {
* false : ...0000 0100 (mrb_fixnum(v) != 0)
* true : ...0000 1100
* undef : ...0001 0100
- * symbol: ...SSS1 1100 (use only upper 32-bit as symbol value with MRB_64BIT)
* symbol: ...SSS1 0100 (symbol occupies 20bits)
* fixnum: ...IIII III1
* float : ...FFFF FF10 (22 bit significands; require MRB_64BIT)
* object: ...PPPP P000
*
- * and word boxing without inline float:
+ * and word boxing without inline float (MRB_WORDBOX_NO_FLOAT_TRUNCATE):
* nil : ...0000 0000 (all bits are 0)
* false : ...0000 0100 (mrb_fixnum(v) != 0)
* true : ...0000 1100

boxing_word.h: fix the error in the comment [ci skip]