added comments


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@3380 a1c6a512-1295-4272-9138-f99709370657
diff --git a/docs/CONTRIBUTING b/docs/CONTRIBUTING
index 1ad6a08..50c57df 100644
--- a/docs/CONTRIBUTING
+++ b/docs/CONTRIBUTING
@@ -27,6 +27,10 @@
 Variables and function names should be all lower case.
 Preprocessor symbols should be all uppercase.
 
+Comments
+--------
+We only use plain old /* C standard comments */.
+
 Style
 -----
 When changing code, follow the code style of the file you are editing.