Fix fastsearch for UCS2 and UCS4
* If needle is 0, try (p[0] >> 16) & 0xff for UCS4
* Disable fastsearch_memchr_1char() if needle is zero for UCS2 and UCS4
diff --git a/Objects/stringlib/ucs4lib.h b/Objects/stringlib/ucs4lib.h
index be1206a..988ddc0 100644
--- a/Objects/stringlib/ucs4lib.h
+++ b/Objects/stringlib/ucs4lib.h
@@ -6,6 +6,7 @@
#define FASTSEARCH ucs4lib_fastsearch
#define STRINGLIB(F) ucs4lib_##F
#define STRINGLIB_OBJECT PyUnicodeObject
+#define STRINGLIB_SIZEOF_CHAR 4
#define STRINGLIB_CHAR Py_UCS4
#define STRINGLIB_TYPE_NAME "unicode"
#define STRINGLIB_PARSE_CODE "U"