sys/log: Re-add LOG_MODULE_PERUSER
This constant was removed in a recent commit
(46a14478933942708562e33a4650f2fede37342e).  We should keep this
constant around to maintain backwards compatibility.  Applications may
define their own log modules with IDs based on this constant.
@@ -67,6 +67,7 @@ struct log;
#define LOG_MODULE_IOTIVITY 7
#define LOG_MODULE_TEST 8
+#define LOG_MODULE_PERUSER 64
#define LOG_MODULE_MAX (255)
#define LOG_ETYPE_STRING (0)
