xenstored: use correct conversion specifier in the tracing function

Previous change to xenstored used "%d" to format conn->id while in fact
conn->id has "unsigned int" type, so "%u" should be used.

Fixes: 97f8555acb ("xenstored: print domain id in traces")
Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
Reviewed-by: Juergen Gross <jgross@suse.com>

tools/xenstored/core.c

@@ -135,7 +135,7 @@ static void trace_io(const struct connection *conn,
 	now = time(NULL);
 	tm = localtime(&now);
 
-	trace("io: %s %p (d%d) %04d%02d%02d %02d:%02d:%02d %s (",
+	trace("io: %s %p (d%u) %04d%02d%02d %02d:%02d:%02d %s (",
 	      out ? "OUT" : "IN", conn, conn->id,
 	      tm->tm_year + 1900, tm->tm_mon + 1,
 	      tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec,