Pull down the DSI_EN gpio to disable mipi dsi panel before booting kernel.
This avoids display full yellow screen before kernel mipi driver probes
the device.

For MIPI2HDMI card, this DSI_EN gpio is not used. So nothing impact to it.

Signed-off-by: Ye Li <ye.li@nxp.com>
(cherry picked from commit e73adc9a139f2e8bb92bda1631fa2f2391a8a5e3)