Get rid of `__` prefix which is presereved by C standard

compile.c

@@ -6902,7 +6902,7 @@ compile_call(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, in
             if (bf == NULL) {
                 if (strcmp("inline!", builtin_func) == 0) {
                     int inline_index = GET_VM()->builtin_inline_index++;
-                    snprintf(inline_func, 0x20, "__builtin_inline%d", inline_index);
+                    snprintf(inline_func, 0x20, "rb_compiled_inline%d", inline_index);
                     builtin_func = inline_func;
                     args_node = NULL;
                     goto retry;

tool/mk_builtin_loader.rb

@@ -29,7 +29,7 @@ def collect_builtin base, iseq_ary, bs, inlines
           raise "1st argument should be string literal" unless prev_insn[0] == :putstring
           text = prev_insn[1]
 
-          func_name = "__builtin_inline#{inlines.size}"
+          func_name = "rb_compiled_inline#{inlines.size}"
           inlines << [func_name, [lineno, text, params]]
           argc -= 1
         end