This patch is in response to the discussion here:
http://sourceware.org/ml/gdb-patches/2012-04/msg00328.html

2012-04-16  Siva Chandra Reddy  <sivachandra@google.com>

        * CONTRIBUTE: Add "cvs diff -up" as a way to generate patches
        when accessing the CVS repository.  Add a note saying that the
        "-up" flavors of "cvs diff" and "diff" are preferred.

Thanks,
Siva Chandra