Fix Nexus 5 (hammerhead) boot and solve framebuffer issue at startup.
This Merge request solves linux-postmarketos#5 (comment 107549300)
With these modifications:
*The nexus 5 boots 100% of the time (tested 15 times in a row)
*The splash screen appears every-time as well.
*Most probably FDE becomes possible, since we can display on framebuffer (not tested yet).
This may also improve boot for other devices.