atm: idt77105: Drop needless setup_timer()

Calling setup_timer() is redundant when DEFINE_TIMER() has been used.

Cc: Chas Williams <3chas3@gmail.com>
Cc: linux-atm-general@lists.sourceforge.net
Cc: netdev@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>