mfd: ti-lmu: Add LM36274 support to the ti-lmu

Add the LM36274 register support to the ti-lmu MFD driver.

Signed-off-by: Dan Murphy <dmurphy@ti.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>