arm/dts: omap3-beagle: Add twl4030 and i2c EEPROM

Add required clock frequencies for the i2c client devices existing
on beagle board.

Add the twl4030 basic description with only the twl_rtc module.

Add the EEPROM node.

Based on original patch from Manju:
http://www.spinics.net/lists/linux-omap/msg55831.html



Signed-off-by: Benoit Cousson <b-cousson@ti.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Rob Herring <rob.herring@calxeda.com>