omap3: id code detection 3525 vs 3515

The runtime detection of OMAP3515 and OMAP3525
was reversed.

Signed-off-by: Sergey Lapin <slapin@ossfans.org>
Signed-off-by: Sanjeev Premi <premi@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>