glacier-panel: Replace blank/unblank code

With more commonized code from vivo.

This is working fine on my Sharp panel.

Signed-off-by: Luis Cruz <ljc2491@gmail.com>
glacier-panel: Finalize panel changes

... for now

Partly based on evervolv's commit a6782e4e

Signed-off-by: Luis Cruz <ljc2491@gmail.com>