1.LDO ramp up time may be modified by ROM code
according to fuse setting, cpu freq driver use
fixed delay time which assume the LDO ramp up time
is the reset value of ANATOP register, need to set
it to reset value in regulator init.

2.The regulator set voltage should take care of
the ramp up time, calculate the ramp up time based
of register setting and to the delay, make sure that
when the set voltage function return, the voltage is
stable enough.

3.CPUFreq no need to use delay, it is already taken
care by regulator voltage setting.

Signed-off-by: Anson Huang <b20788@freescale.com>