drivers: power: pmic: Add support for tps659412 PMIC

Since TPS659412 and TPS659413 are both software compatible,
add a compatible string for the same inside tps65941.c.

Signed-off-by: Sinthu Raja <sinthu.raja@ti.com>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>