ARM: dts: OMAP5: Align the local timer dt node as per the current binding code

It has been decided to not duplicate banked modules dt nodes and that is
how the current arch timer dt extraction code is.

Update the OMAP5 DT file accordingly.

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Benoit Cousson <benoit.cousson@linaro.org>