Code of Conduct: Change the contact email address

The contact point for the kernel's Code of Conduct should now be the
Code of Conduct Committee, not the full TAB.  Change the email address
in the file to properly reflect this.

Acked-by: Chris Mason <clm@fb.com>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Theodore Ts'o <tytso@mit.edu>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>