Revert "msm: mdss: control backlight level during blank and unblank events"

This reverts commit e5ef657e53be7a777ed39b373cbcde0a07d56de7.
Revert "msm: mdss: avoid clocks on if panel is not on for command mode"

This reverts commit 2f9088c217931f2b7cf36b5042bb7faf775dea96.