Fix a compiler warning in unicode_encode_ucs1()
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index 541ded8..e76f069 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -6557,7 +6557,7 @@
 static PyObject *
 unicode_encode_ucs1(PyObject *unicode,
                     const char *errors,
-                    int limit)
+                    unsigned int limit)
 {
     /* input state */
     Py_ssize_t pos=0, size;