omap: Fix wrong jtag_id for 850

Original message:
The previous value of the jtag_id was set for the omap730.  For the
omap850, this value is different, and this was causing
autodetection to fail.

Reported-by:
  Cory Maccarrone <darkstar6262@gmail.com>
  Angelo Arrifano <miknix@gmail.com>
  Alistair Buxton <a.j.buxton@gmail.com>

Signed-off-by: Angelo Arrifano <miknix@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>