mfd: twl4030-power: Remove driver path in file comment

The driver's file path in the comment is wrong, so just remove it since
these tends to get out of date and they serve very little purpose.

Suggested-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>