mx7dsabresd: Set VLD04 output to 2.8V in PMIC initialization.

This change sets the VLDO4 settings output to 2.8V in PMIC
initialization so that the MIPI DSI/CSI input voltage is 2.8V
as per the schematics. The original code provides an output of
3.3V which violates the voltage mentioned in the schematics.

Signed-off-by: Gautam Bhat <mindentropy@gmail.com>
Acked-by: Fabio Estevam <fabio.estevam@nxp.com>