Remove gc_mark_values

Now that gc_mark_values and rb_gc_mark_values are identical, we should
remove one.

gc.c

@@ -6331,16 +6331,6 @@ rb_gc_mark_locations(const VALUE *start, const VALUE *end)
     gc_mark_locations(&rb_objspace, start, end, gc_mark_maybe);
 }
 
-static void
-gc_mark_values(rb_objspace_t *objspace, long n, const VALUE *values)
-{
-    long i;
-
-    for (i=0; i<n; i++) {
-        gc_mark(objspace, values[i]);
-    }
-}
-
 void
 rb_gc_mark_values(long n, const VALUE *values)
 {
@@ -6953,7 +6943,7 @@ gc_mark_imemo(rb_objspace_t *objspace, VALUE obj)
                 // just after newobj() can be NULL here.
                 GC_ASSERT(env->ep[VM_ENV_DATA_INDEX_ENV] == obj);
                 GC_ASSERT(VM_ENV_ESCAPED_P(env->ep));
-                gc_mark_values(objspace, (long)env->env_size, env->env);
+                rb_gc_mark_values((long)env->env_size, env->env);
                 VM_ENV_FLAGS_SET(env->ep, VM_ENV_FLAG_WB_REQUIRED);
                 gc_mark(objspace, (VALUE)rb_vm_env_prev_env(env));
                 gc_mark(objspace, (VALUE)env->iseq);