drivers: video: tidss: tidss_drv: Use kconfig VIDEO_REMOVE to remove video

Perform removal of DSS if kconfigs VIDEO_REMOVE or SPL_VIDEO_REMOVE is
set by user. Otherwise if above Kconfigs are not selected, it is assumed
that user wants splash screen to be displayed until linux kernel boots
up. In such scenario, leave the power domain of DSS as "on" so that
splash screen stays intact until kernel boots up.

Signed-off-by: Nikhil M Jain <n-jain1@ti.com>
Reviewed-by: Devarsh Thakkar <devarsht@ti.com>