internal.h: move rb_readlink declaration

* internal.h (rb_readlink): move the declaration.

* ruby.c (dladdr_path): rb_readlink now requires the result
  encoding.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@51769 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

file.c

@@ -2786,8 +2786,6 @@ rb_file_s_symlink(VALUE klass, VALUE from, VALUE to)
 #endif
 
 #ifdef HAVE_READLINK
-VALUE rb_readlink(VALUE path, rb_encoding *enc);
-
 /*
  *  call-seq:
  *     File.readlink(link_name)  ->  file_name

internal.h

@@ -1266,6 +1266,9 @@ VALUE rb_str2big_gmp(VALUE arg, int base, int badcheck);
 int rb_bug_reporter_add(void (*func)(FILE *, void *), void *data);
 
 /* file.c (export) */
+#ifdef HAVE_READLINK
+VALUE rb_readlink(VALUE path, rb_encoding *enc);
+#endif
 #ifdef __APPLE__
 VALUE rb_str_normalize_ospath(const char *ptr, long len);
 #endif

ruby.c

@@ -382,9 +382,8 @@ dladdr_path(const void* addr)
     }
 #ifdef __linux__
     else if (dli.dli_fname == origarg.argv[0]) {
-	VALUE rb_readlink(VALUE);
 	fname = rb_str_new_cstr("/proc/self/exe");
-	path = rb_readlink(fname);
+	path = rb_readlink(fname, NULL);
     }
 #endif
     else {