ARM: dts: OMAP4: Update timer addresses

For OMAP4 devices, timers 5-8 have both a L3 bus address and a Cortex-A9
private bus address. Currently the device-tree source only contains the
L3 bus address for these timers. Update these timers to include the
Cortex-A9 private address and make the default address the Cortex-A9
private bus address to match the current HWMOD implementation.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Benoit Cousson <b-cousson@ti.com>