OMAP3 Move twl4030 power and led functions

Because twl4030 now has its own device files, move exiting
omap3 power_init_r to a new location.

power_init_r is the only function in board/omap3/common.
It initializes the twl4030 power for the board and enables
the led.

The power part of the the function is moved to twl4030_power_init in
drivers/power/twl4030.c The power compilation is conditional on the
existing config variable CONFIG_TWL4030_POWER.

The led part is moved to twl4030_led_init in the new file
drivers/misc/twl4030_led.c  The led compilation is conditional on
the new config variable CONFIG_TWL4030_LED

The directory board/omap3/common was removed because power_init_r
was the only function in it.

Signed-off-by: Tom Rix <Tom.Rix@windriver.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Heiko Schocher <hs@denx.de>