ARM: dts: omap3: Fix ISP syscon register offset

According to the TRM, SCM CONTROL_CSIRXFE register is on offset 0x6c

Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Reviewed-By: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>