Fix suspend on sun4i.

With this patch A10 actually suspends and resumes by pressing the power
button.

Based on patch by Alexsey Shestacov <wingrime@gmail.com>

Tested-by: Michal Suchanek <hramrach@gmail.com>
Suspend framebuffer on sustem suspend.

Signed-off-by: Michal Suchanek <hramrach@gmail.com>