Buck regulator 1, 2 and 3 of TPS6594132 on j721e-sk is in 3 Phase
confguration, in-order to support this, add configuring 3 Phase buck
in tps65941 while driver probing.
Signed-off-by: Sinthu Raja <sinthu.raja@ti.com> Acked-by: Jaehoon Chung <jh80.chung@samsung.com>