update japanese language by Naoaki Okazaki


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@8987 a1c6a512-1295-4272-9138-f99709370657
diff --git a/docs/CREDITS b/docs/CREDITS
index b0bb823..906e3d0 100644
--- a/docs/CREDITS
+++ b/docs/CREDITS
@@ -177,4 +177,5 @@
 Jani Kinnunen
 Rui Marinho
 Alun Thomas
-Nils Wallménius
\ No newline at end of file
+Nils Wallménius
+Naoaki Okazaki