numeric.h: remove 2 functions from MRB_API

- `mrb_float_to_str()`
- `mrb_float_to_cstr()`

Both functions will be replaced to support new coming `format-float.c`.

include/mruby/numeric.h

@@ -161,15 +161,15 @@ mrb_int_mul_overflow(mrb_int a, mrb_int b, mrb_int *c)
 # endif /* MRB_USE_FLOAT32 */
 
 MRB_API mrb_value mrb_float_to_integer(mrb_state *mrb, mrb_value val);
-MRB_API mrb_value mrb_float_to_str(mrb_state *mrb, mrb_value x, const char *fmt);
-/* ArgumentError if format string doesn't match /%(\.[0-9]+)?[aAeEfFgG]/ */
-MRB_API int mrb_float_to_cstr(mrb_state *mrb, char *buf, size_t len, const char *fmt, mrb_float f);
 MRB_API mrb_float mrb_as_float(mrb_state *mrb, mrb_value x);
 
-/* internal function(s) */
+/* internal functions */
 mrb_float mrb_div_float(mrb_float x, mrb_float y);
+/* ArgumentError if format string doesn't match /%(\.[0-9]+)?[aAeEfFgG]/ */
+mrb_value mrb_float_to_str(mrb_state *mrb, mrb_value x);
+int mrb_float_to_cstr(mrb_state *mrb, char *buf, size_t len, const char *fmt, mrb_float f);
 
-/* obsolete function(s); will be removed */
+/* obsolete functions; will be removed */
 #define mrb_flo_to_fixnum(mrb, val) mrb_float_to_integer(mrb, val)
 #define mrb_to_flo(mrb, x) mrb_as_float(mrb, x)
 

src/fmt_fp.c

@@ -410,7 +410,7 @@ fmt_core(struct fmt_args *f, const char *fmt, mrb_float flo)
   }
 }
 
-MRB_API mrb_value
+mrb_value
 mrb_float_to_str(mrb_state *mrb, mrb_value flo, const char *fmt)
 {
   struct fmt_args f;
@@ -425,7 +425,7 @@ mrb_float_to_str(mrb_state *mrb, mrb_value flo, const char *fmt)
   return str;
 }
 
-MRB_API int
+int
 mrb_float_to_cstr(mrb_state *mrb, char *buf, size_t len, const char *fmt, mrb_float fval)
 {
   struct fmt_args f;
@@ -445,7 +445,7 @@ mrb_float_to_cstr(mrb_state *mrb, char *buf, size_t len, const char *fmt, mrb_fl
 #else   /* MRB_NO_STDIO || _WIN32 || _WIN64 */
 #include <stdio.h>
 
-MRB_API mrb_value
+mrb_value
 mrb_float_to_str(mrb_state *mrb, mrb_value flo, const char *fmt)
 {
   char buf[25];